“We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.”
Various Christians take this line from the Declaration to mean that America was founded on Christianity. But of course Jefferson was a deist, and belief in some sort of creator or unifying force was common even among the Greeks. Even Spinoza could talk of God, basically as a synonym for nature. Life was in fact created, and the creator is natural law, including the process of evolution.
Jefferson before all promoted reason: “Question with boldness even the existence of a god; because if there be one he must approve of the homage of reason more than that of blindfolded fear.”
He was no great fan of organized religion: “History, I believe, furnishes no example of a priest-ridden people maintaining a free civil government. This marks the lowest grade of ignorance of which their civil as well as religious leaders will always avail themselves for their own purposes.”
And he called for the separation of church and state: “Believing with you that religion is a matter which lies solely between man and his God, that he owes account to none other for his faith or his worship, that the legislative powers of government reach actions only, and not opinions, I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should ‘make no law respecting an establishment of religion, or prohibiting the free exercise thereof,’ thus building a wall of separation between church and State.”
People have the absolute moral right — and deserve the fully-protected political right — to practice whatever religion they want, or no religion, however they choose, provided they don’t initiate force against anyone else.