Assume that a god exist (so the following "truth" and "lie" will reflect this assumption), but the object person doesn't believe in him. Which of the following is the worse thing for him to do? 1) He preaches the wonders of God, and preaches it as well as an articulate believer. So he basically spreading the words of God, while not believing in God. 2) He constantly preaches that there is no God. In situation 1, he is spreading the "truth", but in his heart, he's lying. In situation 2, he is true to what he believes, but is spreading a "lie."