It has been three decades since the Rt. Rev. C. FitzSimons Allison took his first step away from his life as one of the Episcopal Church's strongest evangelical voices.

That tentative move took place in a small-group discussion during an Episcopal House of Bishops meeting in Kanuga, N.C., during his final year serving as the 12th bishop of the historic Diocese of South Carolina. The topic that day was, "Why are we dysfunctional?"

Allison attacked Episcopal priests and seminary professors who were openly proclaiming their faith in an ancient, erotic, divine spirit "older and greater" than the God of the Bible. There was, Allison said, a clear, ancient word for that -- "apostasy."

Other bishops said they had no problem accepting clergy who were testing the boundaries of ancient Christian doctrines.

After that clash, Allison remained in his pew and declined to share the consecrated bread and wine during a Holy Eucharist with the entire House of Bishops. He didn't publicly discuss this act of broken Communion for several years, but his silent protest was a poignant symbol of early cracks forming in the global Anglican Communion.

Now the 95-year-old bishop has officially resigned his status as an Episcopal bishop, making his departure official. Two weeks ago, he wrote U.S. Presiding Bishop Michael Curry to clarify that he had been received into the Anglican Church in North America -- a body recognized as valid by many Anglican bishops in Africa, Asia and the Global South, but not by the Archbishop of Canterbury or leaders in the U.S. Episcopal Church.

"Some people said that I didn't need to do this, because everyone knows where I stand," said Allison, reached by telephone. "But I felt, the way things have been going, that I still needed to make things official. That's just the way I am."

Allison was ordained as a priest in 1953 and then received a doctorate from Oxford University. He taught church history at the School of Theology at the University of the South and then Virginia Theological Seminary, before serving for five years as rector of Grace Episcopal Church in New York City. He was elected as a bishop in 1980.

While in retirement, Allison has taken several public actions that violated Episcopal canons, such as celebrating the Eucharist with congregations that had chosen to leave the denomination or had been forced to do so. In 2000, he took part in Singapore rites consecrating as bishops two American priests opposed to the ordination of openly gay and lesbian priests and rites blessing same-sex unions.

For years, Allison and his wife Martha have attended Prince George's Church, Winyah, in Georgetown, S.C. This parish was founded in 1721 and its sanctuary was built in 1755, with additions made during repairs after the American Revolution. The parish left the U.S. Episcopal Church in 2012, with the rest of the conservative Diocese of South Carolina. Bishop Allison is listed as "bishop in residence" on the church website.

"At this stage of things, everyone knows that large portions of the church are apostate. That isn't news anymore," said Allison. However, recent clashes over gender theory during the global Lambeth Conference in England were a final sign that many Anglican bishops have "cut all ties to centuries of church teachings on gender, marriage, sexuality and many other doctrines, as well."

While battles over sexuality make headlines, along with years of lawsuits over church properties and trust funds, Allison said the dividing lines among Episcopalians and Anglicans are usually linked to a single controversial word -- "sin." Many mainline Christians no longer agree on how to define words such as "sin," "repentance," "salvation" and even "God."

Thus, the bishop is working on his sixth book, the first since "Trust in an Age of Arrogance" in 2009. The topic, he said, will be the theological meaning of the word "freedom."

"People believe that 'freedom' is when we are free from all restrictions and restraints. But that just can't last. That isn't freedom, according to the Bible," said Allison. "Freedom is connected to our necessity for forgiveness and salvation."

Once again, he said, the modern church faces that troubling word -- "sin."

"If we have no sense of sin anymore," said Allison, "why do we need a Redeemer?"