In the months before Isaac's birth, Brother Yun was in prison. His mother was about to be forced into having an abortion, though seven months pregnant, because she was carrying the child of an enemy of the state. After desperate prayer, the night before she was due to go into a hospital for the operation, she miraculously gave birth.

Isaac met his father for the first time at the age of four. With Brother Yun constantly on the run, and his mother working to...