"the foundation of faith upon which our Constitution rests"???

The Constitution of the United States of America
Preamble
We the people of the United States, in order to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this Constitution for the United States of America.

Forgive me: I can discern no "foundation of faith" in these words.

"Religion" is mentioned once in the Constitution (including Amendments):
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof...
Amendment 1

The derivative, "religious", is likewise mentioned once:
...no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States.
Article VI, paragraph 3

Again, forgive me: I am unable to discern in these words a "foundation of faith" underlying them.

In civic ritual I repeat the words, "under God." I can sing with appropriate emotion, "God bless America." I am an agnostic. I regard my participation in these civic rituals as a concommitant of citizenship, not as a profession of faith. Do I believe in God? No. Do I believe myself a good U.S. citizen? Yes.

I am disturbed by any implication that my non-belief in any way excludes me from civic life, or somehow makes me an inferior, even second-class citizen.

As a good Baptist reads the Bible as a guide to faith, so do I read the U.S. Constitution as a guide to my civic responsibility. I believe it - as THE document which establishes the United States of America - is worthy of study.

The Preamble makes clear that "We the people of the United States... do ordain and establish this Constitution" in order to secure very secular objectives: "to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity."

This is a secular creed, not a religious manifesto.