If there is an all-knowing God who knows the future, then he knows I'm going to sneeze in 10 seconds. But if I do something to control my sneeze, then I have just changed the future. Does this mean there is not an all-knowing God who knows the future, because we have control over our future. This would suggest multiple futures and abolish the theory of God. Or is there some way for there to be multiple futures and an all-knowing God?

If there is an all-knowing God, and if you are able to control your sneeze, then the all-knowing God does not know that you are going to sneeze and does know that you are able to control your impulse to sneeze. Why doesn't God know that you are going to sneeze? Because it's not true that you are going to sneeze-- to the contrary, it's true that you are going to control your sneeze. Since it's impossible to know what is false, it's impossible for an all-knowing God to know that you are going to sneeze.

Assuming that one's death means the end of one's consciousness. What purpose does a belief in God serve that a non-belief in God cannot?

I’ll leave it to others to say what a belief in the existence of God can promise besides belief in one’s own immortality. Yesterday morning, in the “This I Believe” series on NPR, the magician/comedian Penn Jillette reminded me of some of the things that belief in the non-existence of God promises. You can listen to him here .