Say something like, "When we are confronted with the issue of death, it can often make us think about the issues of God, and about our own eternal salvation. Do you ever think about God? Do you consider yourself to be a good person?" Then gently take him through the Law.
If there is any offence, apologize and change the subject. But more than likely you will find that by talking about his personal salvation, it will be like a complete subject change, and therefore there wont be offensive.
If he is bitter at God and that is hindering him from opening his heart, gently let them know that many people have suffered terrible losses in this life, and they have let that suffering bring them to the Cross, and consequently to everlasting life. An analogy that may be helpful is to say that if someone offers to lift you out of quicksand, don't let the fact that you don't like the color of their skin or you can't understand why they are wearing certain clothes, etc., stop you from giving your hand to your rescuer. God offers to lift us out of the quicksand of death itself. Tell him: "Let Him pull you out, and once you are saved, ask your questions. If you don't get an answer in this life, you are guaranteed to get one in the next."