SPRING CITY, Pa. — A United Methodist minister was convicted Monday in a Pennsylvania church trial of breaking church law by officiating at his son’s same-sex marriage, a case that rekindled debate over the policy of the nation’s largest mainline Protestant denomination.

The Rev. Frank Schaefer testified that he tried to follow God’s command to minister to all, even if he disobeyed the Methodist Book of Discipline.

Schaefer, of Lebanon, Pa., said he could have avoided the trial by agreeing to avoid any more same-sex ceremonies. But he declined, noting that three of his four children are gay.

The charges over the 2007 ceremony in Massachusetts came just a month shy of the church’s six-year statute of limitations, after a congregant complained.

Schaefer could face punishment ranging from a reprimand to losing his minister’s credentials after the jury convicted him of breaking church law that bans clergy from performing same-sex wedd ings. The jury will reconvene Tuesday for the penalty phase.

The nation’s largest mainline Protestant denomination accepts gay and lesbian members but rejects the practice of homosexuality as “incompatible with Christian teaching.”

Testifying in his defense Monday, Schaefer said he might have lost what he called his “ritual purity” by disobeying the Methodist Book of Discipline, but said he felt he was obeying God’s command to minister to everyone.

“I love the United Methodist Church. I’ve been a minister for almost 20 years and there are so many good things about the United Methodist Church except for that one rule,” he said.

Schaefer pleaded not guilty at the beginning of the high-profile trial, which is rekindling debate over the denomination’s policy on gay marriage.

A Methodist trial resembles a secular trial in many ways, with counsel representing each side, a judge and jury, opening statements and closing arguments, and testimony and evid ence. Schaefer can appeal a conviction, but neither the church nor the person who brought the charge may appeal an acquittal.

The church’s lawyer, the Rev. Christopher Fisher, told the jury in his opening statement that Schaefer clearly violated the Book of Discipline. He said the complainant, Jon Boger – a member of Schaefer’s congregation – was dismayed and shocked when he learned this year about the ceremony.

Boger, the church’s sole witness, testified he felt betrayed when he found out that Schaefer, who had baptized his children and buried his grandparents, had presided over a gay wedding.

“When pastors take the law of the church in their own hand … it undermines their own credibility as a leader and also undermines the integrity of the church as a whole,” Boger said.

He said he understood Schafer’s motivation.

“It’s his son. He loves his son. In a way I felt bad for him,” Boger said. “But he’s also shown no remorse or repentance, nor has he apologized to anyone.”

When Schaefer chose to hide the marriage from the congregation, Boger said, “It was a lie and a broken covenant.”

But Schaefer testified he had informed his church superiors of his part in the marriage. He said he kept it from his conservative church’s members because it would be divisive.

“I did not want to make this a protest about the doctrine of the church. I wasn’t trying to be an advocate,” Schaefer said. “I just wanted this to be a beautiful family affair, and it was that.”

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