New York Times bestselling author and journalist Ed Klein is making waves with his new book about the presidency of Barack Obama and his religious journey.

Klein's book, The Amateur: Barack Obama in the White House, has stayed in the No. 1 spot since its release, calling out the president's flaws with quotes from some of his closest allies.

As part of his research for the book, Klein conducted a three-hour interview with President Obama's former pastor, the controversial Rev. Jeremiah Wright.

"This was the most unexpected thing of all. [Wright] said that Barack Obama had been steeped in Islam as a young man because he grew up in Indonesia, his family was Muslim, he knew about the Muslim faith," Klein told CBN News about his discussion with Wright.

"And [Wright] said to Barack Obama, 'You are very familiar with the Muslim faith, but you don't know very much about Christianity. I will help you come to a definition of your idea of what Jesus Christ really means,'" he added.

Klein said he then asked Wright if he "actually converted Barack Obama from Islam to Christianity."

"And this is what the Reverend Wright told me. After 23 years of being very intimate with Barack Obama, he said, 'That's hard to say.' It was a very shocking answer," Klein said.

Click play to watch more of Klein's comments to CBN News White House Correspondent Jennifer Wishon.

Also, watch an extended clip below.

-- Follow Jennifer Wishon on Twitter @JenniferWishon.