Ratified June 21, 1788
Rather than include the entire text of the U.S. Constitution, a few lines have been highlighted below to indicate the framers reference towards God and the Christian Religion. Links to the full text can be found within.
ARTICLE I, SECTION 7
"If any Bill shall not be returned by the President within ten Days (Sundays excepted) after it shall have been presented to him, the Same shall be a Law, in like Manner as if he had signed it, unless the Congress by their Adjournment prevent its Return, in which Case it shall not be a Law."
* Although the founders established a government by which all persons would be able to worship as they choose, it was understood that the foundations of civil activity and discourse within the United States would be oriented by and accommodated for the Christian religion as displayed here in Article 1, Section 7. If any other religion, say Judaism or Islam, were afforded the same consideration, the Framers would have included other days (Friday or Saturday) within these exceptions.
"...done in Convention by the Unanimous Consent of the States present the Seventeenth Day of September in the Year of our Lord one thousand seven hundred and Eighty seven and of the Independance of the United States of America the Twelfth In witness whereof We have hereunto subscribed our Names,"
* The entire Christian world dates history according to the birth of Christ, known as B.C. (Before Christ) or Anno Domini (Year of our Lord). Although the Framers could have used a more generic term like C.E. (Common Era) which had been used as far back as 1708, they chose instead this direct reference to Jesus Christ.
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances."
*Contrary to popular belief, there is no mentioned here of a "separation of church and state." As it pertains to religion, this amendment establishes two distinct principles. First, no single religion will be designated as the official state/federal religion. Second, individuals will be able to worship as they see fit without fear of interference or persecution from government. That is it. For more information regarding Thomas Jefferson's mention of "separation of church and state" and the Founders view of this phrase click on the "Summary of the Separation of Church and State."