"I'm obviously very saddened, so what we're hoping for tomorrow is a light sentence," he said.
The trial will resume Tuesday morning, with jurors hearing more testimony and ultimately deciding whether Schaefer will face punishment. That could include a reprimand, a suspension, or a stripping of his ministry. Frank Schaefer embraced supporters and family after the verdict, with some saying, "We love you." He declined to comment, saying he was not allowed to speak until the proceedings were over.
Bishop Alfred Gwinn is the presiding officer in the trial.
A jury of 13 pastors spent the day in a gymnasium in Spring City, Chester County, hearing testimony in a church trial, a rarely used process for deciding religious matters. Jurors left for deliberations around 5 p.m. and reached a verdict about two hours later. More than nine votes were needed for a guilty finding.
Earlier in the day, Frank Schaefer recalled a phone call that would play a role in his decision nearly 10 years later to officiate at his son's wedding in Boston in 2007.
The caller gave a warning: Schaefer's teenage son was gay and considering suicide.
He said that he and his wife questioned their son, and that Tim acknowledged he had cried himself to sleep praying to God to make him "normal." When that did not work, he wondered if the world might be better off without him.
Testifying Monday before a jury of his fellow Methodist pastors and more than 100 observers, Schaefer said he told his son: "You are a beloved child of God. . . . God thinks you're beautiful, because you're his creation. And he loves you."
When Tim Schaefer asked his father years later to officiate at his marriage to another man, the pastor's reply was immediate.
"To have said no to his request would have negated all the affirmations I gave to him for all those years," Schaefer told the jury.
Testimony also came from Jon Boger, the former church member who filed the accusation against Schaefer.
Dozens of congregants and others, many singing hymns and spiritual songs, gathered before 8 a.m. for the proceeding, held at a retreat center. The trial was the first of its kind in the church in nine years, and some said the case had bitterly divided Schaefer's Zion church.
"I'm watching best friends split in two," said Kassie Bennett, 40, of Lebanon, a member of the church since last year and a supporter of Schaefer's. "We're supposed to be a church that stands together. This place was like a warm hug, and it's not like that anymore. This is tearing us apart."
The United Methodist Church has about 12 million members worldwide. It accepts gay members, but church doctrine forbids the performance of same-sex marriages. More than 30 United Methodist pastors from eastern Pennsylvania expressed solidarity with Schaefer by presiding this month over a same-sex union at a Philadelphia church.
Dozens of supporters flocked to the retreat center Monday, holding signs with slogans such as "Love Casts Out Fear." Beverly Rainforth, 64, was one of several who traveled to Pennsylvania from Binghamton, N.Y., where the pastor of another Methodist church faces a similar complaint.
"Most of our congregation is straight," she said. "We just believe this is a really important social issue."
Schaefer did not dispute that he performed the wedding, and he testified that he knew he was violating church doctrine. But he said he did so out of a desire to show love and respect to all human beings in accordance with Jesus' teachings.
"Maybe I've compromised my ritual purity, but I believe that's what Jesus called me to do," he told the jurors.
Boger, who filed the complaint against Schaefer in April, said he was raised attending Schaefer's church, and said all his family's major events had taken place there - weddings, baptisms, and funerals.
He lives out of state and no longer attends church regularly, he said, but rumors that Schaefer had presided over his son's marriage troubled him. He said it undermined the integrity of the church.
"It was a lie and a broken covenant," Boger testified. "When I see him, I see a clerical collar with a shatter across it."
Boger also admitted that his mother, the longtime choir director at the church, had recently clashed with Schaefer to the point where her termination was discussed, but he said that was unrelated to his decision to file the complaint.
He said he was upset that Schaefer appeared to prioritize his love for his family over the oath he swore as a minister, and that Schaefer kept it a secret.
Schaefer testified that he informed his district supervisor of his decision to preside over his son's marriage, but that he chose not to discuss it with his congregation because he did not want to sow seeds of division.
"I didn't want this to be viewed as a protest," he said. "I knew that if I were to share this with my congregation at Iona, it would be very divisive. I decided to be the best pastor and shepherd I could be."