Don't build the engine, grow it: biohybrid miniature robots using living organisms

International Journal of Extreme Manufacturing

Facebook

WeChat
WhatsAppEmail

 

image: 

A muscle ring capable of generating high contractile forces under tetanus stimulation.

view more 

Credit: By Tomohiro Morita, Minghao Nie, and Shoji Takeuchi* Copyright © 2025 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

Engineers attempting to build microscopic robots face a strict physical trade-off: as mechanical devices shrink, their capacity to carry onboard power and navigate complex terrain rapidly diminishes. A new review in the International Journal of Extreme Manufacturing outlines the most promising approach isn't better hardware but "hiring" biology.

By fusing living organisms like bacteria, algae, and insects with synthetic payloads, researchers are creating living biohybrid miniature robots that self-fuel, self-repair, and navigate environments that would paralyze a rigid silicon chip.

The fundamental bottleneck in miniature engineering is the trade-off between structural rigidity and environmental adaptability. Traditional synthetic robots are precise but "dumb" in complex terrains; they lack the active obstacle avoidance and biocompatibility required for the "messy" reality of the human body or disaster zones.

Living biohybrid miniature robots solve this by using the "embodied intelligence" of biology. Instead of coding a complex navigation algorithm, engineers utilize the natural phototaxis of microalgae or the chemotaxis of macrophages to move toward targets instinctively.

The performance metrics of these biological engines now rival or exceed the state-of-the-art in pure synthetics. Bacterial motors, typically only 1 to 3 μm in diameter, can traverse human capillaries as narrow as 4 μm, a feat nearly impossible for rigid micro-machines.

These microorganisms generate thrust forces ranging from 0.5 pN in Escherichia coli to 4 pN in Magnetospirillum species, achieving swimming speeds up to 100 times their body length per second. In larger-scale applications, cyborg beetles equipped with wireless backpacks have demonstrated a navigation success rate of 94% when following predetermined paths through unknown obstacle layouts.

Sticking synthetic payloads to these living motors is the central engineering challenge, and researchers are using a toolkit of molecular "fasteners". Imagine the assembly process through three analogies: Velcro, Superglue, and the Harness. Electrostatic interaction acts like Velcro, using the natural negative charge of a cell membrane to "stick" to positively charged nanoparticles. Covalent bonding, specifically "click chemistry," functions like Superglue, forming a permanent, high-efficiency chemical bond between the organism and its cargo.

For larger organisms like locusts or beetles, engineers use mechanical harnesses, miniature electronic "backpacks", to stimulate neural circuits directly, co-opting the insect’s own control architecture for remote-controlled jumping or flight.

This shift moves manufacturing away from high-energy, high-cost silicon cleanrooms and toward bioreactors. Because these living materials can reproduce, they offer the potential for massive, low-cost "batch production". On the factory floor of the future, we may see distributed networks of these robots used for large-scale environmental cleanup. Already, algae-based robots have demonstrated the ability to selectively capture and remove heavy metals, microplastics, and even viral agents like SARS-CoV-2 from wastewater.

Despite the potential, the transition from lab-scale prototypes to global deployment faces steep hurdles. The "living" nature of these machines means they have shorter lifespans and lower stability than their chemical or mechanical counterparts.

There is also a significant "immune hurdle": a patient's body may treat a bacterial robot as an infection rather than a cure. Researchers are now testing "stealth" strategies, such as camouflaging robots inside the membranes of a patient's own red blood cells to evade detection.

The next stage of development focuses on full autonomy. The goal is to create systems that integrate sensors, navigation, and actuators so that a robot can identify a diseased tissue, move toward it, and release a payload without any external human intervention. While technological and ethical barriers remain, the transition from building machines to partnering with biology is no longer science fiction. It is the new frontier of extreme manufacturing.

---

International Journal of Extreme Manufacturing (IJEM, IF: 21.3) is dedicated to publishing the best advanced manufacturing research with extreme dimensions to address both the fundamental scientific challenges and significant engineering needs.

• Maintained #1 in Engineering, Manufacturing for consecutive years
• Average time to First Decision after Peer Review: 34 days
• Open Access Publishing with APC Waivers

Visit our webpage, like us on Facebook, and follow us on Twitter and LinkedIn.

---

Journal

International Journal of Extreme Manufacturing

DOI

10.1088/2631-7990/ae34f9 

Article Title

Biohybrid miniature robots using living organisms

Article Publication Date

13-Apr-2026

 

Want to shift a group’s opinion? Encourage opponents to sit on the fence

Neutrality can speed up and stabilise collective decisions, new UK study shows.

University of Bath

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

In voting games with human participants, groups shifted their overall decision more quickly and cleanly than when the option of abstention was removed when abstention was allowed.

view more 

Credit: University of Bath

Trying to persuade people to abandon deeply held views often backfires, leaving groups entrenched and unable to move forward. A new study by researchers at the University of Bath in the UK proposes a strategy that is both surprising and more effective: encourage neutrality.

The researchers, led by Professor Kit Yates from the Department of Mathematics, found that when individuals are encouraged to step back and adopt a neutral position – for example by abstaining in a vote – groups become more responsive, decisions become easier to reach, and shifts in consensus happen more smoothly.

Neutrality does not stall progress – it creates valuable breathing space in which people can reassess their stance, making it easier for a consensus to form or for a group to change its mind when circumstances evolve.

Professor Yates said: “Allowing people to take a neutral stance creates breathing space for reassessment, making it easier for a consensus to form or for a group to change its mind.

“By recognising neutrality as a feature – not a bug – of group decisions, our study resolves a long-standing trade-off: you don’t need elaborate, many person dynamics or sophisticated social structures for consensus and flexibility to emerge.

“Instead, once neutrality is allowed as an option, very simple interactions between pairs of individuals, where A influences B or B influences A, are enough to produce the observed group level behaviour.”

In the new study – published today in Advanced Science – the researchers developed a simple mathematical model to explore how groups make decisions. Their model shows that groups can reach agreement in two ways.

One is the familiar route of persuading undecided individuals to join one side. The other, which has received much less attention, is a ‘de-escalation’ route, in which disagreement pushes people into a neutral state before they later choose a side independently.

The team found this de-escalation route to be particularly effective, allowing groups to change direction more quickly. This occurs because the number of active decision-makers becomes smaller when more individuals become neutral, giving chance a greater influence and allowing a new consensus to form faster.

Neutrality is an option for both animals and humans

The researchers tested their finding in two real systems: locusts and humans.

In marching locusts, they found clear evidence that whenever a swarm switches direction – from one direction to another – it first enters a brief phase where many locusts stop moving, effectively becoming neutral.

With most of the group paused, only a small minority remains on the move. Those few individuals have a much stronger influence on what happens next. This temporary shrinking of the active group magnifies small fluctuations, allowing a new collective direction to take hold quickly.

Next, the team ran voting games with human participants and found that when abstention was allowed, groups shifted their overall decision more quickly and cleanly than when the option of abstention was removed.

The researchers envisage their behavioural insight scaling from animal groups and voting games to boardrooms and online communities. The findings suggest practical strategies for adaptive decision making: if you want to overturn an entrenched consensus, it can be more effective to cool down strong opponents so they adopt a neutral stance, rather than targeting only the stereotypical ‘floating voter’.

“It might be annoying when someone is on the fence about an important topic that you feel passionately about, but in fact this can be a useful strategy to help groups make better decisions in the long run,” said co-author Professor Tim Rogers.

“Our model and experiments suggest a de escalation tactic speeds up responsive consensus change.”

The team carrying out the study were University of Bath academics Professors Kit Yates and Tim Rogers from the Department of Mathematics, Dr Janina Hoffmann from the Department of Psychology and Dr Andrei Sontag, (now at University College London).

---

Journal

Advanced Science

DOI

10.1002/advs.202512301 

Method of Research

Experimental study

Subject of Research

People

Article Title

Consensus Formation and Change are Enhanced by Neutrality

Article Publication Date

23-Mar-2026

 

Worming out molecular secrets behind collective behavior

Indian Institute of Science (IISc)

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Swarm formation in casy-1 mutant worms, demonstrating aggregate feeding and coordinated movement across the food lawn boundary

view more 

Credit: Navneet Shahi

Studying social behaviour is crucial for understanding how certain neuromodulatory pathways – like the serotonin pathway, which influences mood and social interactions – are regulated. 

Kavita Babu, Professor at the Centre for Neuroscience (CNS), Indian Institute of Science (IISc), and her lab have been investigating these signalling mechanisms using the worm Caenorhabditis elegans. In a new study published in the Proceedings of the National Academy of Sciences, they report that the disruption of a single conserved synaptic gene alters the signalling of a specific neuropeptide, resulting in the worms showing an unusual type of swarming behaviour. This swarming resembles serotonin-driven swarming described in other species, such as desert locusts, suggesting that neuromodulatory control of social behaviour might be evolutionarily conserved. 

Navneet Shahi, PhD student at CNS and first author, was initially working on mutant worms for a different project when she noticed something unexpected. Instead of dispersing towards food that was nearby, like wild type worms, these mutants preferred to swarm collectively instead, even if it resulted in starvation. This behaviour appeared repeatedly and reproducibly over multiple experiments.

In order to delve deeper into this phenomenon, the IISc researchers reached out to physicists at Koç University, Turkey, who modelled the movement of the worms. Together, the team found that this behaviour was “self-emergent” and that even a single worm could give rise to group-level swarming over multiple generations – a novel finding. 

Using genetic manipulation techniques like CRISPR, the team then generated mutants lacking a specific gene coding for a protein called CASY-1. CASY-1 is a distant relative of the conserved calsyntenin protein found in higher organisms including humans. The mutation in CASY-1 was found to disrupt signalling by a neuropeptide called pigment dispersing factor (PDF). This essentially unlocked serotonin signalling pathways that are usually kept in check, driving the worms into their crowded, swarming state. Studying these targeted genetic mutants led the researchers to ask the broader question of whether the roots of social behaviour might be genetically encoded. 

The researchers also wanted to see if they could control this behaviour in real time via optogenetics – using light pulses to instantly activate or silence specific neurons and watching whether the worms huddled or dispersed. Capturing this behaviour in a time-lapse video was “intriguing,” says Babu.  

“Initially, we suspected the role of pheromones or external environmental factors in this aggregative behaviour. However, we soon realised that was not the case,” adds Shahi. They found that serotonergic signalling was the master regulator, essentially “tuning” how these worms interact as a group.

While social feeding behaviours have been studied by researchers in the past, such collective movement is relatively less explored. This piqued Shahi’s interest in investigating the molecular pathways involved. C. elegans also makes for a great model system mainly due to its well-characterised nervous system and the ease of studying population-level behaviours within a short period of time, especially those arising repeatedly and reproducibly. 

In future studies, the team plans to investigate how specific genetic perturbations produce different outcomes under varying environmental conditions, in order to understand fundamental rules governing collective behaviour across species. 

 

Network-like aggregation patterns formed by casy-1 mutants under starvation conditions

Credit

Navneet Shahi

Time-lapse video of swarm formation in casy-1 mutant worms, demonstrating aggregate feeding and coordinated movement across the food lawn boundary [VIDEO] 

---

Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2520029123 

Article Title

Neuromodulation of swarming behavior in C. elegans: Insights into the conserved role of calsyntenins

Article Publication Date

27-Feb-2026

Ash Wednesday protests and Masses make solidarity with immigrants a Lenten theme

(RNS) — Chicago Cardinal Blase Cupich told immigrants that Trump administration deportation efforts had acquainted them with Ash Wednesday’s Scripture passage about practicing faith in secret.

Cardinal Blase Cupich participates in a procession through Melrose Park after an Ash Wednesday Mass at the Shrine of Our Lady of Mount Carmel, Wednesday, Feb. 18, 2026, near Chicago. (Video screen grab)

Aleja Hertzler-McCain
February 19, 2026
RNS

(RNS) — Christian leaders — from Catholic cardinals and Episcopal and Lutheran bishops to moderate evangelical Christians — took their faith’s day of penitence and prayer as an opportunity to speak out on behalf of immigrants and against President Donald Trump’s mass deportation campaign. Ash Wednesday began and ended with Masses led by two of the three current cardinal archbishops, with vigils at the White House and in New York’s Federal Plaza, the center of federal government in the city, in between.

In his homily at a large outdoor Mass in solidarity with immigrant families in Melrose Park, Illinois, Cardinal Blase Cupich, the archbishop of Chicago, addressed immigrants directly, saying the anti-immigrant environment has brought home to them the day’s Gospel passage about practicing one’s devotions in secret. Deploring the way they have been “treated like dust that can be swept away,” the cardinal told immigrants, “This day is made for you.”

“When you cry in secret, he sees you. When you work hard for your children while no one is watching, he sees you,” said Cupich of God. “When you sacrifice your own comfort to send money back home, you sacrifice to give alms in secret, and he sees you.”

Several Catholic prelates celebrated Mass in immigrant detention centers. Cardinal Joseph Tobin of Newark, New Jersey, was joined by Newark Auxiliary Bishops Pedro Bismarck Chau, Manuel Cruz and Gregory Studerus at Delaney Hall, an Immigration and Customs Enforcement facility. Las Cruces, New Mexico, Bishop Peter Baldacchino celebrated Mass at Otero County Prison Facility and Processing Center in his diocese.

Tobin told RNS after celebrating two Masses for women detained inside Delaney Hall, “It was sad and yet there was a serenity among them, because they’re women of great courage.”

When informed that Tobin had visited Delaney Hall, Kristina Larios, a Rutgers University-Newark student who attended the Mass that Tobin later celebrated at St. Patrick’s Pro-Cathedral in Newark, said: “It’s an issue here, so it’s a good sign that he cares about people in this area. It’s an important issue to me, too.”

Cardinal Joseph Tobin speaks during an Ash Wednesday Mass at St. Patrick’s Pro-Cathedral, Wednesday, Feb. 18, 2026, in Newark, N.J. (RNS photo/Fiona Murphy)

Sister Susan Francois, a Sister of St. Joseph of Peace, joined members of the Catholic peace organization Pax Christi USA outside the cathedral to thank Tobin for his advocacy. “I am here today at the pro-cathedral to support Cardinal Tobin, who has spoken out in the name of what Christianity and people of goodwill are about,” said Francois, who prays outside Delaney Hall several times a week and offers support to visitors to the detention center.

In some places, faith leaders’ access to detention centers was not guaranteed or simple. The Coalition for Spiritual and Public Leadership, a Christian organization, won a preliminary injunction last week allowing the group access to a nearby detention center in Broadview, Illinois, to provide ashes and Communion on Ash Wednesday. But it was noon on Wednesday before CSPL announced that the Department of Homeland Security had told the group a delegation of two priests and a sister would be able to enter Broadview at 3 p.m.

The Rev. Alex Gaitan, the Archdiocese of Newark’s immigration ministry coordinator, told RNS the process to gain clearance to celebrate Mass at Delaney Hall included a signed agreement from Tobin and the auxiliary bishops to only provide religious services in the center.

In Chicago, Cupich told RNS on Wednesday morning that the purpose of the Mass was to “express our solidarity with people who feel as though fear right now is gripping their hearts.”

Cupich said his primary motivation in crafting the homily was to preach the gospel. “The word of God gives us those images, so my job is to try to make them meaningful to the people who are coming to Mass.”

Cardinal Blase Cupich, top right, celebrates an Ash Wednesday Mass at the Shrine of Our Lady of Mount Carmel, Wednesday, Feb. 18, 2026, in Melrose Park, Ill. (Photo by Steven P. Millies)

In Manhattan, the Episcopal bishop of New York and a Lutheran bishop participated in a prayer service outside the building where immigrants have been detained and held for days before being moved to other facilities. A lawsuit last year about the facility raised serious concerns about overcrowding and unsanitary conditions.

Bishop Matthew Heyd said in a statement: “Ash Wednesday calls us to remember that we are all created in the image of God. Today’s vigil serves as a call to reclaim our shared humanity from the chaos and cruelty that ICE raids have brought to our neighborhoods.”

According to Heyd’s diocesan office, the procession to Foley Square, also known as Federal Plaza, included more than 300 people, among them Long Island Episcopal Bishop Lawrence Provenzano, New York Bishop for the Evangelical Lutheran Church in America Katrina Foster and Episcopal Bishop Suffragan Allen Shin.

The Rev. Winnie Varghese, dean of the Episcopal Cathedral of St. John the Divine; J. Antonio Fernández, CEO of Catholic Charities of New York; Ravi Ragbir, executive director of the New Sanctuary Coalition; the Rev. Paul Brandeis Raushenbush, president of the Interfaith Alliance; and the Rev. Liz Theoharis, executive director of the Kairos Center for Religions, Rights & Social Justice, were also at the Manhattan event.

Delaney Hall Immigration and Customs Enforcement detention facility on Wednesday, Feb. 18, 2026, in Newark, N.J. (RNS photo/Fiona Murphy)

In Washington, D.C., activist groups held Ash Wednesday services near the U.S. Capitol and the White House. A coalition of Catholic groups held a service across the street from the Capitol emphasizing nonviolence, where they prayed about “the horrific ICE raids and killings,” military action in Venezuela, Palestine, Iran and threats against Greenland and Cuba, as well as cuts to social services and climate change protections.

Leaders from Sojourners, Faith in Action, the Georgetown Center on Faith and Justice, the National Council of Churches and the Latino Christian National Network held a separate vigil outside the White House “to issue a moral call to repentance, love, and courageous action in a time of deep crisis for both faith and democracy.”

Several among the group outside the White House also signed onto an Ash Wednesday letter of over 2,000 faith leaders that called the current government and Trump administration “cruel and oppressive.”

“We are facing a cruel and oppressive government; citizens and immigrants being demonized, disappeared, and even killed; the erosion of hard-won rights and freedoms; and a calculated effort to reverse America’s growing racial and ethnic diversity — all of which are pushing us toward authoritarian and imperial rule,” the letter said.

Saying that silence in this moment is not neutrality, but an active choice to permit harm, the letter said, “We call on all Christians to join us in greater acts of courage to resist the injustices and anti-democratic danger sweeping across the nation.”

Fiona Murphy and Jack Jenkins contributed to this report.

Opinion

An Ash Wednesday 'mobilization' showed us a way out of our country's mess

(RNS) — Led by Cardinal Blase Cupich, the crowd prayed and marched with love and without chaos.

People begin a procession through the suburb of Melrose Park, Ill., after an Ash Wednesday Mass at the Shrine of Our Lady of Mount Carmel, Wednesday, Feb. 18, 2026, near Chicago. (Photo by Steven P. Millies)

Steven P. Millies
February 19, 2026
RNS

(RNS) — The Shrine of Our Lady of Mount Carmel is nestled among the well-kept homes of the working-class Chicago suburb of Melrose Park. On Ash Wednesday (Feb. 18), an altar had been erected under a tent outside the church surrounded by a thick crush of 2,000 people who prayed, sang and jostled our way through the ritual. (Fifteen hundred more were somewhat more comfortably inside the church.) When it came time to distribute first ashes, then the Eucharist, there were no neat lines, no aisles or pews — the church building housed only the overflow crowd who would have otherwise blocked the street.

But this was not chaos. Strangers united by faith and peaceful purpose were patient with one another, helped each other. We knew why we were there.

RELATED: Cardinal Tobin leads Ash Wednesday Masses inside New Jersey ICE facility

Illinois Sen. Dick Durbin and the local congressman, U.S. Rep. Chuy Garcia, prayed outside with us. They were not the most honored guests, however; nor was Cardinal Blase Cupich, the archbishop of Chicago, who had come to preside at the Mass. We were there to hold up the family members and other loved ones of residents of Chicago who have been detained, deported or disappeared by the Trump administration. The delegation represented all of those who have been tormented, taken and killed since last year. It was this group who came directly behind Cupich in the procession that began the Mass, the place normally reserved for the most senior cleric presiding at Mass.

That gesture identified these immigrant families and those they represented with the Jesus whose mission, death and resurrection we were there to commemorate.

The cardinal’s homily struck that same theme — uniting mistreated immigrants with God’s love. Cupich seized on the image of dust present in the reminder given on Ash Wednesday as the ashes are imposed on the foreheads of the faithful: “Remember you are dust, and to dust you will return.” Lamenting the suffering of “those who are made to feel like dust,” he observed that dust is found “in construction, in cleaning, in harvesting crops from the fields” — varieties of work that support many immigrant families.

He recalled that God “got down into the dust” when God created us. God “touched” the dust, “molded” it, breathed life into it to create each of us. “You may be undocumented in the eyes of the state,” he said, “but you were handcrafted by the creator of the universe. Your worth does not come from a visa or a permit; it comes from the breath of God inside you.”

Cardinal Blase Cupich delivers a homily in English and Spanish during an Ash Wednesday Mass at the Shrine of Our Lady of Mount Carmel, Wednesday, Feb. 18, 2026, in Melrose Park, Ill. (Video screen grab)

The Mass at Our Lady of Carmel was the latest “mobilization” organized by the Coalition for Spiritual and Public Leadership — so-called, said CSPL board chair Anthony Williams before the Mass, because they are opportunities to resist the Trump administration’s immigration enforcement strategy in an unusual, prayerful, peaceful way. They are meant to remind believers that “Our faith calls us not only to pray but to act.”

Most of all, these mobilizations unite the church to the families and others affected most by the administration. The events allow them to see and feel the presence of the whole church gathered to support them — both the swollen crowd that spilled out into the neighborhood and in the person of Cardinal Cupich, known to be close to Pope Leo XIV, who grew up in another working-class Chicago suburb.

When the Mass ended, hundreds of us processed through the neighborhood, walking behind a banner saying, in English and Spanish, “God’s Love Knows No Borders.” We moved through the streets in silence, holding candles, pausing to recite a decade of the rosary at stops along the way. Sorrowfully, we remembered all of the suffering the Trump administration has created. Many, I expect, prayed that all of this would come to an end. For my own part, I thought of something we had heard in the Ash Wednesday Mass: “Rend your hearts, not your garments.”

Those words of the Hebrew Prophet Joel are among the first we hear in the Ash Wednesday liturgy. Joel wrote amid disaster, centuries before Christ came. A plague of locusts had devastated the land, and a feeling that God had abandoned them haunted the Kingdom of Judah. Yet Joel heralds God’s promise. God waits for them. All they must do is return to God sincerely. A conversion that is inward, not just some outward show, is all God desires. God will be there when we are ready to return.

What does it mean for a people to return to the better version of themselves? What is required? How do we do it?

Anything we do together as a people, we must do both cooperatively and also each alone. Our way has to be like the thick crowd at the Mass, forgoing disorder and chaos. Uncountable individual choices to be patient, to smile, to give way to someone else made that crowd a people united to become the best version of what human beings in action together can look like. We did it each ourselves, and we did it all together.

It has to be like that procession through the streets, a protest, yet no shouting, no destruction of property. There was no disorder, no matter how angry we all were about all that has happened. That Mass and procession showed that a different way is possible.

This way is not easy. It requires a deeply felt sense of shared purpose — even faith. It demands a real change of heart, each of us singly and all of us together as a people. It cannot be forced. To turn a people into a better direction requires something else. It must be given an opportunity. It must be prompted. It must be invited. But each person must decide for change before their choices begin to make change.

This is why CSPL’s mobilizations are so effective, and so promising. Pairing prayer with action brings the witness of faith to the public square attractively, and the experience of it invites each of us to reflect on how we’re engaging the challenges we face in this moment. Not inconsiderably, these mobilizations also pose a real alternative to the anger and violence we see almost everywhere else.

For Catholics, the church is “the mystical body of Christ,” a living presence of Jesus. As much as the Eucharist, Jesus is present in his people in the communion of the church. Our social action, for one another and for justice, as effectively expresses what we believe as prayer does. The more that mystical body moves and acts among the people, enlivened by prayer and united by purpose in peace, the more effectively we will call this people through conversion to return.

For one night it seemed more than possible that, gathered as that mystical body to surround the delegation of family members with our encouragement, support and presence, we can be a better people. We can be better even than what we were before.

(Steven P. Millies is the author of “Joseph Bernardin: Seeking Common Ground” and “A Consistent Ethic of Life: Navigating Catholic Engagement With U.S. Politics.” The views expressed in this commentary do not necessarily reflect those of Religion News Service.)

400 Christian leaders urge resistance to Trump administration on Ash Wednesday

WASHINGTON (RNS) — The statement’s signers include a mix of denominational leaders, seminary presidents, scholars and leaders of prominent congregations.

Federal immigration officers deploy tear gas after the fatal shooting of a U.S. Immigration and Customs Enforcement observer on Jan. 24, 2026, in Minneapolis. (AP Photo/Abbie Parr)

Jack Jenkins

February 18, 2026
RNS

WASHINGTON (RNS) — A group of nearly 400 prominent Christian leaders called President Donald Trump’s administration “cruel and oppressive” and accused the government of being corrupted by an aberrant form of Christianity, in an Ash Wednesday (Feb. 18) statement.

The statement, provided exclusively to Religion News Service in advance, has a list of signers that includes a mix of denominational leaders, seminary presidents, scholars and leaders of prominent congregations. In it, they urged fellow faithful to commit to “greater acts of courage to resist.”

“We are facing a cruel and oppressive government; citizens and immigrants being demonized, disappeared, and even killed; the erosion of hard-won rights and freedoms; and a calculated effort to reverse America’s growing racial and ethnic diversity — all of which are pushing us toward authoritarian and imperial rule,” reads the letter, which organizers said was spearheaded by a group of Christian leaders who have been meeting regularly to discuss how to respond to the administration.

The document raises concerns about “an endangered democracy and the rise of tyranny” and warns of a crisis born out of a “Christian faith corrupted by the heretical ideology of white Christian nationalism, and a church that has often failed to equip its members to model Jesus’s teachings and fulfill its prophetic calling as a humanitarian, compassionate, and moral compass for society.”

“We call on all Christians to join us in greater acts of courage to resist the injustices and anti-democratic danger sweeping across the nation,” the letter reads. “In moments like this, silence is not neutrality — it is an active choice to permit harm.”

The letter also appears to make a thinly veiled critique of House Speaker Speaker Mike Johnson, a Southern Baptist who published a theological defense of Trump’s mass deportation efforts earlier this month. Whereas Johnson argues that the biblical call to welcome the stranger is directed to individual Christians instead of governments, the signers of the letter say otherwise.

Speaker of the House Mike Johnson, R-La., gestures as he meets with reporters at the Capitol in Washington, Tuesday, Feb. 3, 2026. (AP Photo/J. Scott Applewhite)

“Jesus gives His final test of discipleship in Matthew 25:31-46, making clear that the measure of our faith is revealed in how we treat those who are hungry, thirsty, sick, strangers, or imprisoned,” the letter reads. “To say, as some do, that this passage is only about taking care of fellow Christians is an incorrect theological interpretation. It is for the nations, ethnoi, for all peoples.”

Signers include Bishop Vashti McKenzie, president of the National Council of Churches; Bishop Hope Morgan Ward of the United Methodist Church’s Council of Bishops; the Rev. Jihyun Oh, stated clerk of General Assembly of the Presbyterian Church (USA); Bishop Darin Moore, presiding prelate for the Mid-Atlantic Episcopal District of the African Methodist Episcopal Zion Church; David Emmanuel Goatley, president of Fuller Seminary; Jennifer Herdt, senior associate dean for academic affairs at Yale University Divinity School; the Rev. Corey D. B. Walker, dean of Wake Forest University School of Divinity; UMC Bishop Minerva Carcaño; the Rev. Otis Moss III of Trinity United Church of Christ; David Cortright, professor emeritus at the University of Notre Dame’s Kroc Institute for International Peace Studies; and the Rev. Randall Balmer, who holds the John Phillips Chair in Religion at Dartmouth College.

The signers also include several longtime faith-based activists, such as Bishop Dwayne Royster of Faith in Action, Pastor Shane Claiborne of Red Letter Christians, the Rev. Adam Russell Taylor of Sojourners and the Rev. Jim Wallis of Georgetown University’s Center on Faith and Justice.

The statement adds to growing faith-led resistance to the president’s agenda that has erupted over the past year, particularly in opposition to his immigration policies. In addition to statements and sermons issued by religious leaders — including Pope Leo XIV — condemning various policies, more than 100 clergy and faith leaders have been arrested while protesting Department of Homeland Security actions over the past year, and others have been pepper sprayed or shot with pepper balls and pepper rounds.

In addition, dozens of denominations, religious groups and individual houses of worship — as well as several individual faith leaders — have sued the administration over the last year claiming violations to their religious freedom.

Promotional banner for A Call to Christians. (Courtesy image)

The letter outlines a series of theological principles, such as standing with vulnerable people, saying Christians must “defend immigrants, refugees, people of color, and all who are in harm’s way.” Citing various Scripture passages, signers also called on believers to love their neighbors, “speak truth to power,” seek peace, “do justice,” strengthen democracy, “practice hope” and be “rooted and grounded in prayer and love.”

The statement closes with a call to action and a spiritual warning.

“If we as Christians fail to speak and act now — clearly, courageously, and prophetically — we will be remembered not only for the injustices committed in our time, but for the righteous possibilities we allowed to die in our hands,” the letter reads. “History and future generations will record our choices, but the God of Heaven and Earth will judge our faithfulness.”

Some of the letter’s signers — leaders from Sojourners, Faith in Action and Georgetown University — also plan to hold an Ash Wednesday vigil outside the White House on Wednesday, where organizers say they will “issue a moral call to repentance, love, and courageous action in a time of deep crisis for both faith and democracy.”