Actually there is a specific reason for that. The Framers did not mention God as prevalent in the nation's Constitution because they were concerned about the dangers of a national religion and they felt that the states, sovereign at the time, would only elect good Christian men to office. The states were free to establish state denominations, which some did, but there was not to be a national denomination. They assumed, wrongly, that this nation by default would be a Christian nation because the separate and sovereign states would do their duty.
Of course this relies on federalism to some extent and we know full well what the Republican party did to that concept
They assumed, wrongly, that this nation by default would be a Christian nation because the separate and sovereign states would do their duty.
OK, so since they didn't mention God or religion, you're saying they didn't bother because it was so obvious it wasn't necessary?
I have a feeling that no matter what the Federal Constitution said, with the possible exception of "All must worship Satan" you'd be able to spin it into them really meaning to establish the US as a Christian nation even though they didn't actually say it.