Rev. Rick Warren on Easter Sunday said he believes that churches which have accepted gay marriage are weak.

The 58-year-old Warren is the founder and senior pastor of the Lake Forest, California-based megachurch Saddleback Church and the author of the best-selling book The Purpose Driven Life.

Appearing on ABC's This Week, Warren told guest anchor Jake Tapper that his opposition to sex outside of a heterosexual marriage has made him unpopular.

“Do you think there will come a time when Saddleback Church needs to adjust its position on same-sex marriage in the same way that churches have throughout the years adjusted their position ... for instance on divorce? ” Tapper asked after noting that a majority of Americans support marriage equality.

“The Bible's the word of God. And I don't have a right to change it. Policies come and go over the years. And so, if I'm unpopular for certain beliefs, well then I'm unpopular for certain beliefs. And to me the Bible is very clear that sex is for a man and a woman in marriage only. That makes me extremely unpopular. Why? Because I don't believe in pre-marital sex. I believe sex is only for marriage between a man and a woman. And it has a purpose. Why? Because I believe the Bible.”

“But certainly your church has members who have engaged in pre-marital sex?”

“Of course.”

“And I'm wondering if the church, in order to continue to thrive, might have to adjust its policy on same-sex marriage?”

“Actually, history shows that when the church accommodates culture it weakens it,” Warren said. “This is why there is a very weak church in Europe today. It's almost non-existent.” (The video is embedded in the right panel of this page. Visit our video library for more videos.)