September 17 is Constitution Day, marking the day of the signing of the document at the Constitutional Convention in 1787. (It took a little over 9 months, until 21 June 1788, for the Constitution to be ratified.) You may notice a familiar phrase towards the end, which is cribbed from the oath of office required of all federal employees, as mandated by 5 U.S.C. §3331. This, in turn, is derived from the Presidential oath mandated by the Constitution itself.
Almighty God, Author of our life and liberty: we give thee thanks for the grace which thou bestowedst upon the framers of the Constitution of the United States, and for the enduring resilience of their handiwork. Guided by thy Spirit, these visionaries crafted a document which hath been a beacon of hope and freedom for generations, and a touchstone of civic decency for all nations. Grant us, we beseech thee, the will and the strength to support and defend our Constitution from all enemies, foreign and domestic, and the diligence to ensure that all our citizens reap the benefits of this marvelous work; through Jesus Christ our Lord. Amen.