Courtesy: Diocese of South Carolina

The Rt. Rev. Mark Joseph Lawrence, the Episcopal bishop of South Carolina, believes his denomination is moving too far left.

The Rt. Rev. Mark Joseph Lawrence, the Episcopal bishop of South Carolina, fears for the future of his church.

One week after the U.S. Episcopal Church overwhelmingly voted to approve a provisional rite for blessing gay unions and the ordination of transgender people, Bishop Lawrence said in an interview with NBC News that his denomination is moving too far out of the mainstream.

"Do I think that these two decisions will cause further decline? I believe they will," Bishop Lawrence said. "I think we've entered into a time of sexual and gender anarchy."

Lawrence's comments come amid a growing debate over the future of so-called mainline Christian churches: Episcopalians, Presbyterians, Methodists, some Lutherans and more. These denominations, which are generally more liberal than their evangelical counterparts, have been in decline for decades, a trend some observers attribute to their supposed leftward drift.

In a recent New York Times editorial, columnist and author Ross Douthat tackled the "looming extinction" of liberal Christianity, adding that: "Practically every denomination — Methodist, Lutheran, Presbyterian — that has tried to adapt itself to contemporary liberal values has seen an Episcopal-style plunge in church attendance."

Since 2000, the Episcopal Church has lost more than 16 percent of its membership. This decrease reflects a wider trend across most other Protestant denominations. In 2008, the Pew Forum on Religion & Public Life reported that "the proportion of the population that is Protestant has declined markedly in recent decades."

Following the Episcopal Church's decision to adopt gay-union rites last week, most of the Diocese of South Carolina’s delegation left the General Convention to show their concern.

"I had an issue of conscience in which I believed that a line had been crossed in the church’s teachings, that I could no longer pretend that nothing significant had happened," Bishop Lawrence said, adding that the departure of the deputies should not be understood as a departure from the Episcopal Church.

“It’s not merely a matter of adapting the Church’s teachings about Jesus Christ, about salvation, about right and wrong to the culture," he said. "The culture is adrift in sexual confusion and obsession.”

But Jenna Guy, an Episcopalian from Iowa, said when the gay-rites vote was taken that the issue is important to the younger generation of Episcopalians and that the resolution would bring more people into the church.

"It’s always with great pride that I tell [people] of the inclusive nature of this church,” Guy said. 

The Episcopal Church's approval of the rites makes it one of the more liberal churches on that issue.

• In May, the United Methodist Church, the largest mainline denomination in the United States with about 7.8 million members, voted against changing its definition of marriage as between a man and a woman.
• Earlier this month, the U.S. Presbyterian Church narrowly rejected a proposal for a constitutional change that would redefine marriage as a union between "two people" rather than between a woman and a man. The church, with around 2 million members, currently allows ministers to bless gay unions but prohibits them from solemnizing gay civil marriages.
• The Evangelical Lutheran Church in America defines marriage as "a lifelong covenant of faithfulness between a man and a woman" and has no official rite for same-gender unions.
• Standing out among the rest, the United Church of Christ, a mainline Protestant denomination with about 1 million members, voted in 2005 to support full civil and religious marriage equality for same-sex couples.

"I see other mainline denominations that are fairly liberal, like the Presbyterians and the Methodists, just really being very careful about jumping over this hurdle," David Hein, Hood College historian and co-author of “The Episcopalians,” a history of the church, told NBC News, "because it really wreaks havoc with the denominations for the national headquarters on down, the institutions, the seminaries, the parishes when you start to lose huge numbers of members.”

"I think churches that are fairly clear in their stance and are not either fundamentalist or way out there on the fringe are doing pretty well," Hein added.

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Steady decline in membership, however, is a problem across the board for mainline Protestant churches.

According to the National Council of Churches' 2011 report, membership in the UCC declined 2.8 percent to 1.1 million members over the previous year; the Presbyterian Church was down 2.6 percent to 2.7 million; the Episcopal Church was down 2.5 percent to two million members and the Evangelical Lutheran Church was down 2.0 percent to 4.5 million members.

The United Methodist Church's membership has declined every year since it was formed in 1968, according to a 2010 report commissioned by the denomination.

In the case of the Episcopal Church, Hein believes it "might not have been hemorrhaging so quickly " had it been more accommodating of its traditionalists.

“I think it’s a mistake that the Episcopal Church is not more welcoming of the mainstream attitude,” he said, adding that "these accommodations should really have been made five, seven years ago, because really about all that’s left of the Episcopal Church is the left wing of the Episcopal Church.”

In 2003, the election of the first openly gay bishop in the Episcopal Church caused a deep rift between liberals and conservatives within the global Anglican Communion, with many churches leaving the U.S. and affiliating instead with the global Anglicans. The Episcopal Church is an independent church affiliated with the worldwide Anglican Communion.

"I still believe there is a broad and silent middle [within the Episcopal Church], I just don't know what it would take for them to stand up with moral courage and say, 'We don't believe this,'" Bishop Lawrence said.

Bucking the national trend, the Diocese of South Carolina experienced growth in 2011 in its average Sunday attendance, which rose 10.8 percent, from 11,086 to 12,286, according to the diocese.

“If ever there was a time for the church to be clear, hopeful, and to offer a moral compass to the struggling, and grace, and forgiveness, and healing to the broken, it’s now,” Bishop Lawrence said.

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