The American unit of Pax Christi, worldwide Catholic peace fellowship, last weekend voted not to join a coalition of religious groups being formed to support the SALT II treaty.

The Most Rev. Thomas J. Gumbleton, auxiliary bishop of Detroit who is president of Pax Christi USA, told a convention of the organization in New York City that the proposed arms limitation treaty would not decrease the danger of nuclear warfare.

"Even the most limited appraisal of SALT II leads clearly to the conclusion that this agreement would not in any meaningful way limit nuclear arms," Gumbleton told the national Pax Christi assembly, held at Columbia University.

On the contrary, he charged, the proposed SALT agreement would leave both sides with massive quantities of armaments.

"To me it [SALT agreement] appears to be hardly more than a cruel hoax," the bishop said. "We would continue to live in a world where the United States and the Soviet Union together would have firepower two million times greater than was used by all combatants in World War II."

The Pax Christi annual meeting preceded a widely publicized two-day convocation on disarmament sponsored by Riverside Church in New York. under a new emphasis on peace and disarmament launched by the church's pastor, the Rev. Dr. William Sloane Coffin.

In an address to that convocation, Coffin likened Pentagon planners to cult leader Jim Jones and called American planning for nuclear war and preparations for civil defense "the Kool-Aid drill without the cyanide."

Building on the same comparison, Richard Barnett, cofounder of the Institute for Policy Studies, charged that "like the people of Jonestown, we have lost control over our leaders."

The Rev. Dr. Robert McAfee Brown, professor of Ecumenics and World Christianity at Union Theological Seminary in New York, described as "a form of madness" the continued stockpiling of weapons despite the fact that more weapons diminish rather than increase security.

Brown said that "our society is made up of fearful people. But in the national security state, we give up our own popular sovereignty to the military... put our trust in computers... and surrender our ability to control our own destiny."

The United Presbyterian theologian urged Christians to follow the example of the prophets by refusing to conform to the "madness" of confemporary society. Brown asserted that evil structures must be redeemed and if need be, overthrown.

At a public liturgy for peace, Rep. Ronald V. Dellums (D-Calif.), chairman of the Congressional Black Caucus and a member of the House Armed Services Committee, said that in 1967, the secretary of defense determined that 400 hydrogen warheads were adequate to deter Soviet aggression, a number already on hand.

"Why then is there a call to arms?" he asked, suggesting that part of the answer lies in what he called a new right-wing political philosophy of promoting weapons at the expense of people.