June 7, 1797 John Adams signed the Treaty of Tripoli. Article 11 states "The government of the United States is not in any sense founded on the Christian religion."

The Founding Fathers were Calvinists, Unitarians and Free Thinkers, not Christians.

Thomas Jefferson:

I have examined all the known superstitions of the world, and I do not find in our particular superstition of Christianity one redeeming feature. They are all alike founded on fables and mythology. Millions of innocent men, women and children, since the introduction of Christianity, have been burnt, tortured, fined and imprisoned. What has been the effect of this coercion? To make one half the world fools and the other half hypocrites; to support roguery and error all over the earth.

Here's Thomas Paine:

I would not dare to so dishonor my Creator God by attaching His name to that book (the Bible).
Among the most detestable villains in history, you could not find one worse than Moses. Here is an order, attributed to 'God' to butcher the boys, to massacre the mothers and to debauch and rape the daughters. I would not dare so dishonor my Creator's name by (attaching) it to this filthy book (the Bible).