The Rev. John Dear, a prominent peace activist and Jesuit priest, has left the Society of Jesus — the same order Pope Francis belongs to—after years of disagreements with Jesuit leaders.

Dear said he and the order cut ties—a highly unusual move for a Jesuit, who takes solemn, lifelong vows to the community—because the society did not support his social activism.

“I’m leaving because the Society of Jesus in the U.S. has changed so much since I entered in 1982 and because my Jesuit superiors have tried so hard over the decades to stop my work for peace,” Dear wrote in a Jan. 7 column for National Catholic Reporter, the liberal weekly that he writes for.

But church sources said the two sides parted ways only after a years-long effort to persuade him to fulfill the communal responsibilities expected of all Jesuits. They said Dear’s superiors had tried to find ways to allow him to continue his peace ministry, which is the sort of activism that Jesuits have become known for and which has been highlighted by Francis.

The termination decree signed by the head of the international order, the Rev. Adolfo Nicolas, was dated June 19 and says that Dear has been “obstinately disobedient to the lawful order of Superiors in a grave matter,” according to NCR, which first reported the dismissal.

The decree further states that Dear had been ordered to return to his community by a certain date or face dismissal. The Society of Jesus provided no further details on the circumstances surrounding the expulsion. Dear is a member of the Maryland province of the Jesuits, one of seven regions of the society in the U.S.

Dear, who has been arrested dozens of times while engaging in civil disobedience for various causes, has long been known as something of a Lone Ranger type in an order that is known for its social activism but also for its powerful communal ethos and its strict vows of obedience. That includes a special vow of obedience to the pope.

Francis is the first Jesuit to become pope; he apparently played no role in Dear’s dismissal, which followed a unanimous vote by the six members of the Jesuits’ international council. It was unclear whether Francis has or would eventually have to confirm the dismissal.

For now, Dear remains a priest, though he said he is “not sure if I will remain a priest.” He cannot function as a Catholic priest unless a bishop gives him permission to do so. Dear said he is continuing to work for peace and justice with other organizations.

Dear’s column in NCR explaining his decision provided some insights into how alienated he had become from his community.

In the essay, Dear repeatedly blasted his superiors, often by name, saying he suffered under their “authoritarianism” and that their behavior had a “debilitating effect” on his health. He accused the Jesuits of abandoning him but also their larger, historic commitment to the poor.

Several Jesuits said privately that Dear’s charges were unfounded, and they pointed to Pope Francis’ own speeches as well as to the myriad efforts for social justice that the Jesuits operate and support.

Dear acknowledged that he had been ordered to return to Baltimore from New Mexico, where he led protests against nuclear weapons development at the Los Alamos National Laboratory.

His activities and preaching there had upset many Catholics who were often the target of his pointed criticisms. Three years ago, he said, Archbishop Michael Sheehan of Santa Fe had withdrawn permission for Dear to work as a priest in the archdiocese.

Dear detailed a litany of other conflicts with the order but said that when he was told he would have to spend time working at a Jesuit-run high school in Maryland, he instead took a leave of absence and moved back to New Mexico. He said he finally asked to leave the society, and this week formally did so.