How do we know that God exists?


My 18 year old son works with a middle aged man who is seen as very smart by his fellow employees. This man talks a lot to his younger co-workers and insists there is neither God nor hell. He says that God can not know all things, create all things, etc. He asked this question: If God can make anything can he create a rock that is too heavy to be lifted by even God? Please direct me in helping my son respond. Apparently this man has read a lot of the bible and seems to have great come backs that send these poor young men reeling. Thank you and God bless you all!!


Dear d,

That line is as old as the hills. There are others like it: “Can God create a square circle?” and so on. They all require God to contradict Himself. To contradict Himself WOULD be a weakness. But remaining consistent is not a sign of weakness.

God cannot sin either. This is not a weakness. God cannot be other than He is (all powerful, all knowing, all good). These are not weaknesses.

To walk by an automobile parked at the curb and suggest that such a contraption could come together by chance, with all its various types of metal and leather and rubber, etc—is absurd. How could anyone posit such a thing? And yet the world and all it holds is far more complex than an automobile. Creation demands a Creator.

Fr. Vincent Serpa, O.P.

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