This quotation has proliferated widely on the internet and though it seemed at first a bit suspect, it turns out to accurate. The full quotation and citation are as follows:
“It is from the Bible that man has learned cruelty, rapine, and murder; for the belief of a cruel God makes a cruel man.”
Thomas Paine -- "A letter: being an answer to a friend, on the publication of The age of reason." Paris; May 12, 1797.
This letter was originally printed in The Prospect, Or View of the Moral World, published by the blind deist lecturer Elihu Palmer. Insofar as I can tell, the recipient is unknown.