Warren will deliver the invocation during the presidential inauguration ceremony today. The Warren selection has angered homosexual lobbyists and pro-choice advocates. Warren is a theological conservative who opposes homosexual marriage and abortion.

He is the pastor of one of the largest churches in the United States - the Saddleback Community Church in Lake Forest, California - which has 30,000 persons attending on weekends.

From the outset, Warren set out to be different. While in seminary, he wanted to be a missionary. But when he realised that was not his calling, he did a study of the largest churches in the United States and discovered some principles that he adapted for his own ministry.

In 1979, he and his wife Kay founded a church in Saddleback Valley, California, with a mission unlike the others. There were many strong Bible-teaching churches in southern California, but Warren intentionally sought out people who did not regularly go to church.

Largest churches

Two weeks after the couple arrived in the Saddleback Valley, they began with a small Bible study, meeting with one other family in the Warrens' small condo.

On Easter of 1980, Saddleback Valley Community Church held its very first public service and 205 people, most of whom had never been to church, showed up. That begun a journey which has so far resulted in Warren becoming the pastor of one of the largest churches in the United States.

Purpose-driven philosophy

Saddleback offers more than 200 community ministries and support groups for parents, families, children, couples, prisoners, addicts, among other people living with HIV/AIDS.

The church today has four campuses in California: Lake Forest, Corona, Irvine and San Clemente.

To date, more than 200,000 church leaders from around the world have been trained in Saddleback's purpose-driven philosophy.

In 1995, he wrote the best-seller The Purpose Driven Church and in 2002 published The Purpose Driven Life.