Much debate over whether the U.S. was founded as a Christian nation. (Some of my forebears knew it wasn't a Christian nation because it refused to acknowledge God in the Constitution, and therefore until 1830's refused to perform civic duties which would require oaths.)
The National Archives has a daily "Today's Document". Today's is the "Secrecy Agreement"--after the Continental Congress had declared independence of George III, they started to get scared. So they all signed an agreement in the fall of 1776 to keep their discussions secret. Interestingly, although it's a solemn agreement, it doesn't include any swearing. The fearsome consequence of leaking was to be treated as an enemy to American liberty.