Article VII of The Constitution states "The ratification of the conventions of nine States shall be sufficient for the establishment of this Constitution between the States so ratifying the same. 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 independence of the United States of America the twelfth. In witness thereof, we have hereunto subscribed our names." By using the words "year of our Lord" the writers and ratifiers of the Constitution not only acknowledged God, but recognized Jesus as Lord.

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I do believe that it was during the Eisenhower Administration when the opening prayer was instituted in Congress. It was not until then that this occurred. It was also done to strengthen the idea that we (our citizens) refuted Communism. That was the first time "In God We Trust" was added to our currency.

FYI: In the last census it was found that there were more agnostic and atheists - listed as "none"s - when asked about church affiliation.

Bzzzzt! Incorrect! By using the words "year of Our Lord", they referred to the specific calendar they were using to mark the date. At the time of the constitutional convention, many differing calendars were in use across the globe. The words "year of Our Lord" refer specifically to the Christian calendar as indexed to the birth of Jesus Christ. Hence the "year of Our Lord" is a direct reference to the number of years after Christ's birth, not some religious sleight of hand.

So how many calendars are there? A lot. An awful lot:

https://en.wikipedia.org/wiki/List_of_calendars

'WHY GOD IS IN THE DECLARATION BUT NOT THE CONSTITUTION'
https://allthingsliberty.com/2016/02/why-god-is-in-the-declaration-but-not-the-constitution/

No country venerates its “Founding Fathers” like the United States. Academics, legislators, judges, and ordinary citizens all frequently seek to validate their opinions and policy prescriptions by identifying them with the statesmen who led America to nationhood. It is not surprising, therefore, that debates about the role of religion in the United States are infused with references to the faith of the Founding Fathers and to the two greatest documents they gave to the fledgling republic: the Declaration of Independence and the United States Constitution. People across the religious spectrum, from the most devout believers to the most committed atheists, look to these documents for support. Yet the blessings they offer are mixed. The Declaration contains several references to God, the Constitution none at all. The reasons for this variation reveal a great deal about the founding principles of the United States.

The Declaration of Independence is an apology for revolution. Support for a complete break with Great Britain was growing stronger week by week in the spring of 1776, both in the Continental Congress and in the thirteen colonies at large. On June 7, 1776, a resolution advocating independence was presented to Congress by Richard Henry Lee of the Virginia delegation. Four days later Congress appointed a committee of five delegates to draft a document explaining the historic separation it would soon be voting on.

The resulting Declaration of Independence, drafted by Thomas Jefferson and edited by his fellow delegates, contains a theory of rights that depends on a Supreme Being, not man, for its validity. The Declaration states that “all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.” It is possible to see in these words an affirmation of the Founders’ religious faith, but God-given rights had less to do with theology in the summer of 1776 than they did with rebellion.


In stating that people’s rights were given to them by their creator, the Continental Congress endowed those rights with a legitimacy that knows no parallel in mortal sources. What God has given to man is not enjoyed at the sufferance of any monarch or government. Liberty is the inviolable birthright of all. The right of revolution proclaimed by the Declaration flows directly from this notion of inviolability: it is to secure people’s divinely endowed and unalienable rights that governments, “deriving their just powers from the consent of the governed,” are established. The people consequently have the right and indeed the duty to alter or abolish a form of government that becomes tyrannical.

The Declaration contains several other references to a higher power. The introduction states that the “Laws of Nature and Nature’s God” entitle the American people to a separate and equal station among the powers of the earth. In the conclusion, Congress appeals to “the Supreme Judge of the world” for the rectitude of its intentions and professes its “firm reliance on the protection of divine Providence.” In each case, reference to a deity serves to validate the assertion of independence.

The genius of the Declaration is the inclusive way the divine is given expression. The appellations of God are generic. Adherents of traditional theistic sects can read the words “Nature’s God,” “Creator,” and “Supreme Judge,” and understand them to mean the god they worship. The claims made on numerous Christian websites attest to this. Yet opponents of dogma read those same words and see an embracive, non-sectarian concept of divinity. This is no small testimony to the wisdom and foresight of the Founding Fathers. All Americans could support the Revolution and independence. All can regard their rights as unalienable, their liberty as inviolable.

Unlike the Declaration of Independence, the United States Constitution contains no reference to God. At first, this may seem odd. Why did the men who drafted the Declaration invoke a Supreme Being several times, while the men who drafted the Constitution did not mention a higher power even once? Only six individuals signed both documents, so it could be hypothesized that the delegates to the Constitutional Convention that convened in Philadelphia in 1787 were a different and less religious group then the delegates to the Continental Congress, or perhaps that the delegates to the Continental Congress were savvy freethinkers cynically manipulating people’s belief in God to win support for their overthrow of British rule. Neither explanation holds water. Some of the Founders were conventional Christians and some were not, but the belief in a deity implied in the Declaration was sincere and likely universal among the delegates to both the Continental Congress and the Constitutional Convention. And a belief in the possibility of divine favor was held by even some of the least religious Founders. So, again, why no invocation of God in the second major founding document?

The threefold answer lies in the stated purposes of the Constitution, its religious neutrality, and the theory of government it embodies. Whereas the Declaration explained and justified a rebellion to secure God-given rights, the Constitution is a blueprint for stable and effective republican government in a free country. The Preamble to the Constitution declares that its purposes are “to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty.” These are wholly secular objects; religious references are extraneous in a document drafted to further them.

Eighteenth century America was religiously diverse, and by the time of the Revolution religion was widely viewed as a matter of voluntary individual choice. The Constitution acknowledged these realities and, unlike contemporary European political orders, promoted no sect and took no position whatsoever on theological issues. There is no state religion and Article VI of the Constitution provides that “no religious Test shall ever be required as a qualification to any Office or public Trust under the United States.” The First Amendment to the Constitution, ratified in 1791, provides that “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof.” The absence of references to a deity in the Constitution is consistent with the strict religious neutrality of the entire document.

The Constitution established a strong national government to replace the relatively feeble Confederation Congress created by the Revolutionary-era Articles of Confederation, but the Constitution is hardly a document glorifying top-down power. On the contrary, the theory of government underpinning the United States Constitution is popular sovereignty. The government derives its legitimacy from the consent of the governed, not from an assembly of elders, not from a king or a prelate, and not from a higher power. The stirring opening words of the Preamble, “We the People of the United States,” make it clear both who is establishing the government and for whose benefit it exists. There is no consent required beyond the will of the people for the people to govern themselves.

This view that the Constitution is a bold assertion of popular sovereignty is often countered by pointing out how elitist some of the delegates to the Constitutional Convention were and how allegedly undemocratic the document they drafted was. Only the members of the House of Representatives were initially chosen directly by voters. Senators were to be chosen indirectly by state legislatures, and the President by electors appointed by the state legislatures.

This criticism confuses an admittedly elitist preference for government by the able with a theory of power emanating from above. The Constitution not only rejected monarchy, but all forms of hereditary privilege and arbitrary rule. It established fixed rules that delimited the powers of the governors, not the rights of the governed. It is to the citizens and the states, not to the executive, that legislators are answerable. The source of all legislative and executive power can be traced, directly or indirectly, to the people.

And in the early years of the American republic, the people in question were deeply suspicious of power. There was considerable opposition to the Constitution as initially drafted, both in the state conventions called to ratify it and among ordinary Americans. Opponents believed that a centralization of authority would lead to tyranny and argued either for outright rejection or, at a minimum, for amendments to limit the powers of the new government and safeguard liberties. In such an anti-power environment, few Americans wished to see their new rulers claim, as European rulers did, that their authority was divine in origin. In creating a political order based on popular sovereignty, the Founding Fathers thus turned prevailing European political theory on its head. In place of the divine right of monarchs, the Declaration asserted the divine rights of all men, and both the Declaration and the Constitution source the legitimacy of political rule exclusively in the consent of the governed.

The Declaration of Independence and the United States Constitution do not therefore represent competing views of the existence of a Supreme Being or its role in American political life. They are two sides of the same coin. When read together, the Declaration and Constitution tell us that the people’s rights are divine in origin, sacred and unalienable, while governments are human in origin, answerable to the people and dependent entirely on their consent.