NEW YORK -- The movement toward legalizing same-sex marriage and the acceptance of gay people as clergy and lay members of religious groups is "a done deal" that represents "phenomenal" progress, the top figure in the Episcopal Church told The Huffington Post during a recent visit to its newsroom.

In an hour-long conversation with HuffPost staffers, the Most Rev. Katharine Jefferts Schori, presiding bishop of the Episcopal Church, touched upon subjects that ranged from her views on how to interpret scripture and challenges that face the church as its demographics change to debates over contraception and the relationship between religion and science.

Jefferts Schori is the first female bishop to lead a province of the Anglican communion, a 85-million member global denomination whose U.S.-based body is called the Episcopal Church. Since being installed in 2006, her tenure has been marked by tensions within the church over the ordination of openly gay bishops. Dozens of Episcopal parishes have left the American church over the issue and have aligned themselves with more conservative Anglican bishops in other parts of the world. The bishop reaffirmed her support for the gay rights movement during her visit.

On same-sex marriage and other gay rights issues, Jefferts Schori said she has been "stunned at how quickly public opinion has changed in the U.S." though she cautioned that she doesn't expect controversy over gay clergy in the Episcopal Church to fade. As more states legalize same-sex marriage, she said, conflicts in the church could become more frequent.

"We muddle through [controversial issues] in a very public way," she said of the church that has just under two million members in the United States.

"I would guess that at [General] Convention, we would adopt a trial rite for blessing same-sex unions," she said, referring to the meeting of the church's governing body, which meets every three years. It will next meet in July in Indianapolis. Jefferts Schori said that no priest is required to bless any marriage, but that formal same-sex blessings could become optional.

She also spoke of the recent controversy over a federal requirement that employers' health insurance plans provide contraception coverage.

The United States Conference of Catholic Bishops has fought against the requirement, which exempts plans provided to employees of houses of worship but in its original version did not exempt those of religious institutions such as Catholic schools and hospitals. President Barack Obama later broadened the exemption to shift the cost of contraception coverage to insurers in cases where a religiously affiliated employer has a moral objection, but Catholic bishops have said that the adjustment still violates their religious beliefs because many Catholic institutions self-insure.

"It's appropriate for couples to plan their families," Jefferts Schori said, adding that contraception is a "normative part of health care." She also said the Episcopal Church "has taken a very nuanced approach on abortion. We say it is a moral tragedy but that it should not be the government's role to deny its availability."

The bishop said that much of the conflict over sexuality among Episcopalians and Anglicans -- and more widely, among Christians -- comes from their differing interpretations of scripture. She warned against taking a strictly literal approach to the Bible.

"The best of scriptural interpretation is about looking at the whole document and the direction in which it is moving rather than pulling out pieces that point to your point of view or prejudice," she said. "When Christians read their scripture that way, they have much more fruitful conversations with Muslims, Buddhists and Sikhs who read their scripture that way."

Jefferts Schori, who was Roman Catholic as a child, was received into the Episcopal Church at the age of eight, after her parents decided to join. She received a doctorate in oceanography from Oregon State University in 1983 and worked as an oceanographer before being ordained as a priest in 1994. She was an assistant rector, hospice chaplain and university lecturer in Oregon before becoming bishop of the Episcopal Diocese of Nevada in 2001.

The bishop said her career as a scientist has influenced her belief that religion and science, which are often painted as incompatible, can coexist. Jefferts Schori said she encourages parishes to tackle issues such as climate change and poverty.

"We are increasingly concerned that the way human beings use resources here in the developed part of the world has an increasing impact on poor people not only here but around the world," she said. "Our part in what we call God's mission is to help heal the world, heal the brokenness of the world."

Like many Protestant denominations, the Episcopal church, which is considered a "middle way" between Roman Catholicism and Protestantism, has declined significantly in membership. In 1966, it had 3.6 million members. A 2010 count turned up 1,951,907 members in the U.S. The church also has 173,105 members in other countries and territories, including the British Virgin Islands, Colombia, the Dominican Republic, Ecuador, Haiti, Honduras, Taiwan and Venezuela.

Jefferts Schori said that she is "not caught up in the numbers game."

"I don't know if people in the 1960s were as well-formed or as well-committed ... It was socially normative to be part of a church in the 50s and 60s," she said, adding that she believes attending church today is a more active decision than it used to be.

"We don't count the right way. How many lives has the work of a congregation touched this year?" she said. "That's a more important question than counting who came to church on a Sunday."