found this... no cheating and looking up the answer riddleme:
Suppose you die and awaken in a room with two doors and one guard at each door. A voice speaks to you and tells you that one door leads to eternity in Heaven and one door leads to an eternity in Hell. You are allowed to approach a guard and ask him a question and only one question that will help you determine which door to choose since the doors are unlabeled and you are unable to look through a door before entering.
However, you are also told that one of the guards ALWAYS lies and one ALWAYS tells the truth, and you cannot know which one is which.
What question do you ask so that, no matter which guard you ask (remember, you CANNOT know which one you are asking), you get an answer that guarantees that you choose the correct door?