This is how Robert Ingersoll responded to a Fundamentalist's question, 'What if it's the truth?' back in the 19th century.
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"Why," they say to me, "suppose all this should turn out to be true, and you should come to the day of Judgement and find all these things to be true. what would you do then?" I would walk up like a man, and say, "I was mistaken.""And suppose God was about to pass judgment upon you, what would you say?" I would say to him, "Do unto others as you would that others should do unto you." Why not?
I am told that I must render good for evil. I am told that if smitten on one cheek I must turn the other. I am told that I must overcome evil with good. I am told that I must love my enemies; and will it do for this God who tells me to love my enemies to damn his? No, it will not do. It will not do."
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