“When you buy the religion subject, you are presented with many stories about heaven, personal experiences about near-death and the afterlife,” Ms. Bostelman said, noting that several other books with “heaven” in the title have sold well recently. “But what was unusual about this book was that it was the story of a little boy. It deactivated some of the cynicism that can go along with adults capitalizing on their experiences.”

Image The book’s cover shows Colton when he was younger.

Todd Burpo wrote the book with Lynn Vincent, who collaborated with Sarah Palin on “Going Rogue.” Mr. Burpo, the pastor of Crossroads Wesleyan Church in Imperial, a farming community in southwest Nebraska, said in an interview that he had shouldered some criticism over it.

“People say we just did this to make money, and it’s not the truth,” Mr. Burpo said, referring to anonymous online comments about the book. “We were expecting nothing. We were just hoping the publisher would break even.” (He said he planned to give away much of the royalty income and spend some of it on home improvements.)

At first, he and his wife, Sonja, were not sure if they could believe their son’s story, which came out slowly, months and years after his sudden illness and operation in 2003. The details persuaded them, Mr. Burpo said. Colton told his parents that he had met his younger sister in heaven, describing her as a dark-haired girl who resembled his older sister, Cassie. When the Burpos questioned him, he asked his mother, “You had a baby die in your tummy, didn’t you?” While his wife had suffered a miscarriage years before, Mr. Burpo said, they had not told Colton about it. “There’s just no way he could have known,” Mr. Burpo said.

And the Burpos said that Colton painstakingly described images that he said he saw in heaven  like the bloody wounds on Jesus’ palms  that he had not been shown before.

Eventually the Burpos decided to tell their story beyond their town. Mr. Burpo, in his Sunday sermons, had already introduced some anecdotes to his congregation. Through a pastor friend, they met Joel Kneedler, an agent with Alive Communications, a Christian literary agency in Colorado Springs. Mr. Kneedler sold the book to Thomas Nelson, a publisher known for Christian titles like “40 Days With Jesus” by Sarah Young. The advance was in the low five figures.