The Rev. David Ousley was baptized a Methodist in 1951, was ordained a priest of the Episcopal Church in 1979, and left it in 1999 for the Anglican Church in America.

And on Saturday, this 61-year-old married father of three will make one more ecclesiastical leap: he will be ordained a priest of the Roman Catholic Church in a 11 a.m. Mass at Holy Cross Church in Mount Airy.

He is "swimming the Tiber," as Anglicans call conversion to Catholicism — a reference to the river that runs through Rome — but the white-bearded Ousley will not emerge from his swim on some strange and foreign shore.

Even after he becomes a Catholic priest, he can continue to wear his Anglican collar, lead his flock at Vesper services, warble old hymns like "A Mighty Fortress," and read some of the prayers found in the lectionary that the Church of England has been using since King Henry VIII broke with Rome in the 16th century .

After decades of petitioning and negotiating by conservative Anglicans and Episcopalians, Pope Benedict XVI in 2009 approved a constitution, called Anglicanorum Coetibus, establishing the equivalent of national dioceses for disaffected Anglicans such as Ousley. These ordinariates, as they are called, allow laity and clergy from the Anglican tradition to join the Roman Catholic Church while retaining much of their liturgies, calendar, and traditions — including married priests.

The ordinariate for Britain was created last year, for the United States and Canada in January, and for Australia on Friday. About 60 Anglican priests and 2,000 laypeople are expected to join the North American ordinariate, headed by the Rev. Jeffrey Steenson, a former rector of the Episcopal Church of the Good Shepherd in Rosemont and a longtime friend of Ousley and his wife, Beth.

"I'm enormously grateful to Pope Benedict because he's given us a new life of being who we are, and more than who we were," Ousley said in an interview at his West Mount Airy home last week.

"While my family and friends might demur if I described myself as a misanthrope, I am certainly not of gregarious temperament," he said in well-enunciated vowels that hint at some blue in his blood. His family settled Massachusetts in 1638, he went to Yale, and he has a doctorate in patristics, or early Christian theology.

His erudite formality can be "intimidating," he conceded, adding, "I don't do well at cocktail parties." And so he is "thrown back on grace" to summon the "welcoming warmth" needed of a parish pastor.

Agree with his reasons or not, his church changings through the decades have been principled and carefully considered.

At Yale he concluded that because preaching — the cornerstone of much Protestant worship — was so variable in its quality, it "was not a sufficient foundation" for Christian worship, and found himself drawn to the eucharistic worship services he encountered in the "high" Episcopal Church, some of whose liturgies are similar to the Roman Catholic. "It was a dimension of the spiritual life I had never known before," he said.

He entered Episcopal seminary after earning his doctorate at the University of Chicago, and was still in formation when, in 1976, the Episcopal Church (the recognized U.S. branch of the worldwide Anglican Communion) approved the ordination of women. "I was not sure I could be ordained in a church that did that," he recalled, but — hopeful the church might reverse itself, and certain it would never oblige all clergy to endorse women's ordination — he was ordained deacon and then priest in 1979.

He served as a curate, or assistant parish priest, in Manhattan and Connecticut until 1983, when the vestry of St. James the Less parish in East Falls called him to be its new rector.

Its active membership was only about 35, but it grew to about 100 during Ousley's rectorship. On Feb. 11, 1989, however, the Episcopal Church ordained the Rev. Barbara C. Harris of Philadelphia a bishop in the Diocese of Massachusetts. It was a move Ousley found even more problematic than the ordination of women and actively gay people, he said, because the bishops in hierarchical churches are understood to be the direct successors of Jesus' apostles.

The ordination of women bishops "was a material act of schism" that not only threatened to sever the line of apostolic succession, he said, but cast doubt on the authenticity of any ordinations that women bishops made.

In 1999, Bishop Charles Bennison of Philadelphia told Ousley and his vestry that "the church has moved on and you haven't. You're out of bounds."

"I think he wanted us to subvert our consciences and get with the program," Ousley said last week. "But we took him to say, 'You're out.' So, we disaffiliated."

A few months after Bennison's admonition, he and the vestry declared St. James disaffiliated from the diocese and no longer Episcopalian, and barred Bennison and other diocesan leaders from teaching or leading sacramental events at the parish. The diocese refused to recognize the disaffiliation, declined the parish's efforts to purchase the property, and, according to Ousley, "made it clear they wanted us to vacate."

A long and draining legal battle in civil courts ensued, ending with the Pennsylvania Supreme Court's 2005 ruling that although St. James indeed owned its church and grounds, an Episcopal parish only holds its property "in trust" for its diocese. Early in 2006 Ousley and all 70 of St. James' parishioners departed and formed a new congregation, St. Michael the Archangel, also a part of the Anglican Church in America.

St. Michael's met for the next few years in the chapel of Laurel Hill Cemetery before the congregation was obliged to decide if it would "swim the Tiber" with its rector. When Ousley announced his intention early this year to seek ordination into the Catholic Church, about 25 of his parishioners joined him when St. Michael's relocated worship services in April to the Roman Catholic Church of the Holy Cross in East Falls.

Most who did not follow him have joined one of two other traditionalist Anglican congregations in the area. Although anyone may worship at St. Michael's, membership in the parish and the new ordinariate is restricted to those who grew up in an Anglican or Episcopalian church.

Because his longtime friend Steenson, who heads the North American ordinariate, is not a bishop (Steenson is married), Ousley will be ordained Saturday by Bishop John McIntyre of the Archdiocese of Philadelphia.

Much remains uncertain about the new ordinariate. The Vatican has yet to adopt an English-language prayer book for its liturgies, and it unclear what its policy on ordaining married men might be in years to come. Still, Ousley says he feels as if he has come home.

"It's nice," he said, "to be able to say, 'This is what the church teaches,' instead of, 'This is what the church ought to teach.'?"

Contact staff writer David O'Reilly at 610-313-8111 or