The Seven Deadlies by Greg Stolze

Love the Sin, Hate the Sinner

Gaviel, a smooth-talking demon who made his way out of hell, finds himself playing the part of Noah Wallace, son and heir apparent to a televangelist mission with bulging coffers. A perfect cover for a devil on the make! Not everything can go according to plan, however. The mad demon Avitu is looking to recruit Gaviel, while the avenging angel Usiel just wants to send him back to Hell. And all the while, the spirit of Noah Wallace is clamoring for its body back, and getting just a little stronger every day.

Even a devil eventually pays his dues.