The Founders knew the Christian Bible. Even those who did not consider themselves to be Christians knew the Bible well and had respect for it. Benjamin Franklin and Thomas Jefferson are generally included among those who are not considered Christians. Yet they often spoke of divine providence, and quoted the Scriptures. From the writings of the people who wrote the Constitution, and argued for it, there is no doubt that the Christian Bible influenced the men who wrote the founding documents, including the Constitution. Entire books have been written about this, a couple of which I have, but I am not going to spend too much time on that here, although I'll probably get back to it later. Of course, other historical forms of government were studied in detail, and these were large influences on the type of government decided upon by the Founders. Other influences included... John Locke, an English philosopher who lived between 1632 and 1704, wrote about his social contract theory, that God gives you certain rights upon birth, and you enter into a government in order to assure those rights are respected. His theory was well known, and accepted by many of those who wrote our nation's early political documents. Montesquieu was a French political thinker who lived between 1689 and 1755. His book, The Spirit of the Law, discusses the separation of powers, similar to to the checks and balances that are supposed to be in place among the three branches of government. William Blackstone was an English judge and jurist who lived between 1723 and 1780. He wrote a book known as Commentaries on the Laws of England, which became a foundation for the legal system in America. There were other influences as well, and I'll probably get back to them later.