Robert "Bobby" Luisi Jr. is a former mob boss turned pastor from Memphis, Tennessee who has vowed never to hurt anyone again.

Luisi's promise is a big one, given the fact he was involved in six murders in the past. "I was involved between Philadelphia and Boston in at least a half a dozen murders,'' Luisi shares with KGW.

He now goes by the name Alonso Esposito after entering a federal witness-protection programme three years ago. Esposito affirms that the "old me is dead. I love being Alonso Esposito. Bobby Luisi's dead and buried. The blood of Christ washed the blood off my hands.''

Luisi used to roll in the dough, getting $40,000 a week just trafficking in cocaine. Aside from drugs, the former mob boss is also known for the 1990 heist of $500 million worth of artwork, which included three Rembrandts, from a Boston museum.

Back then, nobody ever thought that Luisi had it in him to become a preacher, but he now runs Alonso Esposito Ministries.

"The only way I had to fight this thing was the name of Jesus,'' Esposito says. "I [have] seen the power of his name. I have to follow my faith and what the Lord wants me to do. I'm going to tell you I can never hurt anybody again. I have too much love in my heart."

Esposito admits he is ashamed of the things he did in the past, but he is no longer afraid of facing the consequences of his actions. The only thing he's really concerned about now is clearing his name and serving God to the best of his ability.

"See you got to understand something — I never ratted on anybody. No one seems to understand that. Except for that Rico Ponzo, I didn't rat on anybody. So I want you to express that: I'm not a rat and I didn't rat on anybody," he stresses.

Esposito thinks it's a miracle he was able to give up being "a die-hard gangster, murderer, drug dealer, [and] extortionist" after he accepted Christ, and he says he's now "straight as an arrow.''

Of course, there will always be some people who refuse to believe in his sincerity as a Christian. But Larry Easton, former pastor of an interdenominational church in Boston who knew Esposito years ago, believes in his transformation.

"He was very conflicted. His father was deeply involved in the mob and he idolised him," he says.