ST. LOUIS — One of the largest Christian denominations in the country has rejected a plan to allow openly gay pastors, and same-sex marriage.

That was the decision from the United Methodist Church Tuesday afternoon in downtown St. Louis.

The United Methodist Church voted to adopt the "Traditional Plan." That means the church would uphold the language that says homosexuality "is not compatible with the teachings of Christianity" and would add penalties for clergy who break that rule.

It was approved by a vote of 438-384. Opponents unsuccessfully sought to weaken the plan with hostile amendments or to prolong the debate past a mandatory adjournment time set to accommodate a monster truck rally in the arena. One delegate even requested an investigation into the possibility that "vote buying" was taking place at the conference.

The Traditional Plan's success was due to an alliance of conservatives from the U.S. and overseas. About 43 percent of the delegates were from abroad, mostly from Africa, and overwhelmingly supported the LGBT bans.

If the bans were eased, "the church in Africa would cease to exist," said the Rev. Jerry Kulah of Liberia. "We can't do anything but to support the Traditional Plan — it is the biblical plan."

The deep split within the church was evident in several fiery speeches opposing the Traditional Plan.

"If we bring this virus into our church, it will bring illness to us all," said the Rev. Thomas Berlin of Herndon, Virginia. He predicted many Methodist churchgoers and some regional bodies would leave the church, while others would "stay and fight," performing same-sex weddings even if it meant punishment.

There was an alternative plan — the One Church plan — that would give churches and conferences flexibility on LGBTQ ministers. It failed earlier in the day.

About 15,000 Young Methodists under the age of 35 signed a petition urging the United Methodist Church to reconsider this vote on homosexuality. Despite that petition being presented several times Tuesday, it did not sway the vote.

At around 6 p.m., police were called to America's Center where LGBT supporters were protesting the decision. 5 On Your Side's Chris Davis was inside the lobby as supporters protested by singing as police officers looked on.

While other mainline Protestant denominations, such as the Episcopal and Presbyterian (U.S.A.) churches, have embraced gay-friendly practices, the Methodist church still bans them, though acts of defiance by pro-LGBT clergy have multiplied. Many have performed same-sex weddings; others have come out as gay or lesbian from the pulpit of their churches.

Enforcement of the bans has been inconsistent; the Traditional Plan aspires to beef up discipline against those engaged in defiance.

The Rev. Tim Bagwell, 64, pastor at a UMC church in Macon, Georgia, had opposed the Traditional Plan and called the outcome "deeply painful." But he said his church will stay with UMC until at least 2020, when the next major conference is scheduled. He's hopeful new delegates will be elected and change course to a more inclusive church.

In an era where most churches are seeing empty pews, Rev. Matt Miofski isn’t.

“It’s actually the third fastest growing United Methodist Church in the country,” said Rev. Miofski, the Lead Pastor of The Gathering in St. Louis.

After the vote Tuesday, he’s worried that won’t last.

“Right now, we’re clearly a church in conflict - a church that has broken apart. There are people who have strong feelings on one side, we have just as strong feelings on another side and we’re committed to working towards full inclusion,” said Miofski.

He believes it’s entirely possible the church will split in two.

“We are going to have to take a hard look and really begin deliberating on what our larger relationship is with the larger denomination,” he said.

Miofski prays, his congregation will stay united, even if his denomination doesn’t.

“The Gathering will not stop what we’ve always been doing - which means we will continue to welcome LGBTQ people into the whole life of our church,” said Miofski.

The Associated Press contributed to this report.

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