Taken from The Way of the Master Minute
Witnessing to Moslems
If you witness to a Moslem, realize that he will almost certainly acknowledge his sins, but will trust in God to forgive him because he says that he is sorry, and won’t sin again. So, before you open up the Law, tell him the story about a criminal who has committed a very serious crime. He says, “Judge, I am guilty, but I’m sorry and I won’t do it again.” Make sure that the Moslem agrees that if the judge is good, he must punish the criminal. He would be a bad judge if he didn’t make sure justice was done. He cannot simply let him go. Then take the Moslem through the Law, and when he tries to justify himself by saying that he simply asks God to forgive him, remind him of the story you told him about the good judge, and point out that God is infinitely harsher. Then tell him the good news of the cross. There goes another minute. Gone forever. Go share your faith while you still have time.