A publicly devout man or woman who uses their pious reputation to aid in cheating on their partners. Can be either using the excuse of church activities or "ministering" to folk as a cover for their trysts, or making ostentatious public displays of religious contrition to rehabilitate their image after being caught.
Sue: "Wow, Bob's really involved in the Church Choir."
Sam: "Involved with 3 separate women in the choir while his wife watches the kids at home is more like it - he's such a Jesus Cheater."
OR
Sally: "After much prayer, I know that God has forgiven me for my mistakes. I'll pray that he helps you open your heart to his will and find forgiveness as well."
Sally's Husband: "Don't try that Jesus Cheater shit on me! You've been fucking that douche Bob from choir - we're getting a divorce!"
Cowardly married man who cheats with his coworker for years on his wife and family of 16 years and then RUNS away like a little bitch when confronted. Then he moves in with the still married slut with 3 kids from different men.