Just saw an interesting movie about this guy:

https://en.wikipedia.org/wiki/Sam_Childers

In the spring of 1974, shortly before Childers turned 12, his family moved to Grand Rapids, Minnesota. He was going into seventh grade that fall, and the two years before he started high school were some of the most influential times of his life. It was in these formative years that he discovered cigarettes, marijuana, alcohol and heroin, which led to many years of drug addiction, drug dealing, and alcoholism. Childers also developed a love for motorcycles and the lifestyle that often follows an outlaw biker.

Sam eventually married a woman named Lynn, who was a club stripper before converting to Christianity, and had a daughter (Paige) and a son who later died of a heroin overdose.

In mid-1992, Childers converted to Christianity shortly after, and with the help of his wife at a revival meeting at an Assembly of God church. That same evening Childers' pastor prophesied that he would go to Africa. At the end of 1998, Childers made his first trip to Sudan. In that first trip and the many that followed, he was exposed to the acts of the Lord's Resistance Army (LRA) which he described as atrocious. Not long after his first trip to Sudan, Childers and his wife Lynn founded the Angels of East Africa, the Children's Village in Southern Sudan. The Children’s Village currently houses and educates over 300 orphans, with over a thousand children rescued since its conception. The staff at the Children's Village are primarily Sudanese orphans and widows themselves. This is currently the largest orphanage in Southern Sudan and is unique in its approach of leading armed rescue missions directly into LRA territory.

Childers details the events of his life and his experiences in Africa in his book Another Man's War.

In November 2009, Childers appeared on Debra Peppers' television show Outreach Connection in Quincy, Illinois. He revealed that he also rescues children abducted in northern Uganda.

Not sure why the needed Christianity though.