Separation of church and state - a gift of God if ever there was one. Nowhere in the Constitution, the document that prescribes how we are governed, is there any reference to "God," "creator," "divine providence," or any other reference to the supernatural.
In contrast, the Declaration of Independence has several references to the divine - understandably, too. This document was designed to disabuse the people that kings were appointed by God, and therefore their whims must be unquestioningly obeyed. In the declaration, Jefferson does invoke epithets of divine authority (i.e. nature's God, creator, supreme judge) to convince the people that treason against the king is also blessed under circumstances enumerated in the declaration. Our forefathers were trying to convince subjects that suffering under a despot was not divinely inspired and, in the declaration, tailored their words to empower the people to revolution.
I believe the inclusion of references to the divine in the declaration was intentional to rally support for the fight for independence, and the elimination of any reference to the divine in the Constitution was likewise intentional. By deliberately omitting God in our Constitution, the founding fathers conveyed to us their belief that absolute separation of church and state is fundamental to the promise that is America. To that promise, I pray "under God" will not become a part of the pledge.
President, Americans United for Separation of Church and State-Alaska Chapter