CNN —  

Billy Graham was having doubts – in his ministry, in his rock-ribbed Christian faith, even in himself.

At age 30, he was president of a small Christian college in Minnesota. But he was better known as the skinny preacher with the booming voice who crisscrossed the country leading evangelistic crusades.

But the size and ardor of the crowds had begun to wane. After a “flop” in Altoona, Pennsylvania, Graham was almost ready to call it quits.

“It was sorriest crusade we ever had,” said his longtime friend and colleague Grady Wilson.

Even more troubling for Graham: A fellow preacher had been peppering him with questions about the trustworthiness of the Bible, hammering cracks in the bedrock of his faith.

Graham died on Wednesday at age 99. Presidents and pastors mourned his death, calling the evangelist one of this country’s most successful and beloved preachers.

But in August of 1949, Billy Graham was just another lost soul, looking for a little help from above.

Climbing the mountain

Handsome and charismatic, Charles Templeton was every bit the evangelist as Graham. The two friends traveled and preached together during the mid-1940s in the Youth For Christ movement.

More intellectually curious than Graham, Templeton had begun to read modern theology, which threw doubt on the historical accuracy of the Bible. He told Graham their faith was flimsy and urged him to study at a top seminary. The two evangelists wouldn’t be able to get by on their “animal magnetism and youthful enthusiasm” forever, Templeton argued.

Graham demurred, saying he “didn’t have a good enough mind” to settle deep theological questions. Templeton accused his friend of “intellectual suicide.”

Riled by the insult and wracked by doubts, Graham fled to Forest Home, a Christian retreat center tucked into Southern California’s San Bernardino Mountains. There, he wandered among the tall pines and wrestled with his misgivings.

Graham sat on a tree stump and opened his Bible on a big rock. He prayed and pondered, pleaded and struggled, until, finally, he surrendered, deciding to trust in the authority of the Bible, doubts be damned. (A bronze tablet marks the “Stone of Witness” at Forest Home.)

“He decided to simply preach the Gospel and not worry about the intellectual challenges of the faith,” said Randall Balmer, a professor of American religious history at Dartmouth University.

“He literally climbed down the mountain and never looked back.”