Tens of thousands of Seventh-day Adventists are meeting this week to face an issue as divisive as any in the Protestant group’s 152-year history: Does the Bible allow women to be ordained as clergy?

The question has special complexity for Adventists, who to this day revere one of their founders who saw visions — a writer named Ellen White — a woman described in documents from her lifetime as “ordained.”

Discussions about what it means to be ordained, what the Bible says about women’s leadership, what to do with women’s spiritual gifts and whether different regions of the 18-million-member faith can disagree culminate in a vote Wednesday. The vote is considered not only the main event of the July 2-11 General Conference, a meeting Adventists have only once every five years, but to some potentially schismatic.

Western Adventists say the ban on female leaders is holding back their ability to function in this culture, while proponents of the status quo say they read scripture as banning women from overseeing men.

Adventists also are expected to reaffirm two of their fundamental beliefs: that the world was created in literally six days, before God rested, and that marriage is between a man and a woman. These votes, which are not expected to be seriously contested, reflect a recent push by Adventist leadership to keep the faith firmly on orthodox grounds, experts said.

The Silver Spring, Md.-based denomination has been resisting efforts to ordain women for decades, a period in which the Adventist center of gravity has shifted from its American roots to a booming, developing and more theologically conservative world.

In 1950, just a third of Adventists were in Africa and Latin American, whereas today it’s more like 80 percent, said Monte Sahlin, a recently retired regional vice president. Just more than 1 million of the 18 million worldwide live in the United States.

The issue is being pushed in the last couple years since North American Adventists have voted for women to be ordained, and the largest U.S. conference, in Southern California, in 2013 elected Sandra E. Roberts to be its president. The faith’s top executive body doesn’t recognize her leadership, and the space for Southeastern Conference “president” is left blank in the official Seventh-day Adventist directory, or yearbook.

Now the Adventists, a group that has long resisted creating extensive doctrine and rules, are looking at whether they can agree to disagree. Adventists have never allowed for diverse practices on a topic as fundamental as this.

Some say the Adventists could be headed for a split, while others believe most members value the faith’s large size and don’t want to start breaking off chunks. The church is largest in Africa, Central America, the Caribbean and in the northern part of South America.

The debate and shifting demographics are hardly unique to Adventists. As denominations including Anglicanism and Methodism have shrunk in the U.S. and Europe and exploded in the global South, values have changed.

In North America, Adventists are dramatically graying, and the ban on female clergy is a barrier for young people. In many other parts of the world, equalizing gender roles is viewed very negatively, Sahlin said. New Adventists in the Southern Hemisphere are attracted, often from Catholicism, because they like the concept of sectarian separation. They perceive the ordination debate as dangerous, secular feminism, he said.

“All of a sudden the denomination is becoming worldly and part of the culture … people want something more separated from the world,” he said.

On Wednesday, Adventist delegates from 190 countries will be asked whether it is all right for regional bodies “as they may deem it appropriate in their territories, to make provision for the ordination of women to the gospel ministry?”

The conference is drawing 60,000 to 70,000 people, said Garrett Caldwell, spokesman for the global church.

Also being voted on — and expected to pass — is an edit to Adventist doctrine that refers in places to a commitment between “partners.” The new language will make clear that same-sex marriage is against Adventist practice and that marriage is between one man and one woman.

There are of course LGBT Adventists, including unofficial supporting organizations. However, Sahlin said, many have left the faith.

Also expected to pass is a revision to another of the 28 “fundamental beliefs,” reaffirming a belief that God created the world in a week.

The issue has come up in some Adventist colleges and universities, as it has at other conservative Christian schools that are trying to balance a commitment to orthodox practice with a desire for an open academic environment.

“The need for clarification comes because some might look at the seven-day account in the Bible and say, ‘Scientifically, this is impossible.’ Or that the word ‘day’ is symbolic,” Caldwell said. “We’re saying, ‘No, we believe that.’ ”

Christians who say women can’t be clergy come at it from different perspectives. Catholics, for example, focus on the story of Jesus and his male apostles. Traditional Protestant groups, including the Southern Baptists and the Lutheran Church — Missouri Synod, cite scripture calling for women to be students, not teachers or authority figures over men. Many Christian groups that accept women’s leadership either cite sociological reasons or say women who were given spiritual gifts by God should be allowed to use them.

Which is where White comes in. Perhaps the most revered of Adventist founders, White is believed to have had many spiritual visions, and her writings are pored over. While documents say she was “ordained,” there is disagreement about what specifically that meant in her lifetime. A full day at the convention is set aside, Caldwell said, to discuss this issue.

“She was never ordained,” said David Neff, longtime editor of Christianity Today and a former Adventist pastor, “but did all the things ordained people do.”

Clinton Wahlen, associate director of the Adventist Biblical Research Institute, said there is no question White was an “inspired messenger of God” and had credentials as a public speaker and church representative that were as high as any man. But, he said, she never performed a wedding or conducted a baptism — functions clearly reserved for clergy. Wahlen is among those who sees no Biblical basis for women to be ordained clergy.

“There is a clear gender specification that we cannot ignore as a Bible-based church.”

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