The topic was a tough one. Especially in church. Even for a former president, fortified by decades of handling delicate matters in the public eye.

On Sunday, former president and Sunday school teacher Jimmy Carter said he was taking on “how to correlate Christian faith with society’s customs.”

Or as Saint Paul put in one of his letters to the Corinthians, which Carter read to the congregation:

Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body. Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God?

Carter was handling his normal weekly duties at Maranatha Baptist Church in Plains, Ga., where he teaches Sunday school to several hundred folks each week. These sessions have gotten more popular since the 91-year-old announced that he’s battling brain cancer. The church accommodates the hundreds of guests who travel to Plains just to see Carter.

He admitted that he wished he was traveling himself, and thereby unavailable for Sunday’s sensitive lesson.

“I’m a little uncertain on this subject,” he said.

He stepped onto the slippery slope by acknowledging the realities of modern media, and how casual sex before marriage and even outside a marriage seems normal. But he also cautioned the crowd against harsh judgments of people, noting Jesus Christ’s acts of forgiveness, even for a prostitute.

Live as a Christian, but be forgiving of others, Carter emphasized.

“What is the standard I want to set for my own life?” he asked.

He peppered his lesson with political stories, saying “I’m teaching, not preaching.”

The highlight: He went back to his infamous interview with Playboy magazine during his successful presidential campaign.

According to The Washington Post, “Carter admitted in an unsolicited comment to two Playboy freelance writers that he had ‘looked on a lot of women with lust’ and had ‘committed adultery in my heart many times.’”

Carter told the crowd he did the interview because his advisers said it would be a way to reach young voters. He said his comments were misunderstood, and instead should’ve been seen as acknowledging some of the same ideas he was discussing on Sunday.

AJC Editor Kevin Riley spent Sunday in Plains, Georgia, and attended Jimmy Carter's Sunday school lesson and services at Maranatha Baptist Church. Later this week, look for a video and his column about what it was like to be at Sunday school and service with former President Jimmy Carter.