I think the mistake you're making is putting too much emphasis on one quote; a quote that, as I pointed out, could be misleading when the historical context is left out.
Then I will get more general. Get yourself a cup of coffee/tea/cocoa. You're going to want it for this one.
We can focus on Adams, and I still assert that he was not interested in the least in inserting religion (any religion) into the governance of the country, but to gain a true insight into whether or not we were intended to be a "Christian nation," perhaps we should go further afield.
Before we do so, however, I believe it important to remember something: Regardless of their personal religious beliefs, all of them,
all, also believed vehemently that at no time should religion rule the country, nor that the country is founded on any one religion (or any at all).
It is also important to note that at the time, it was extremely difficult to at least not have the appearance of being a "Christian," even if you weren't - which is why the "Founding Fathers" found it so vital that there be no religious reference in the Constitution, and that there should never be an official State religion.
There are several "Founding Fathers," but let's examine them in a little more detail, because what they believed personally isn't really as important as the protections they put in place to ensure that this country would
never be a "Christian nation" or a "Muslim nation" or even a "Flying Spaghetti Monster nation."
George Washington
Washington was a member of the Anglican church, becoming a vestryman in 1762, and a three-term church warden at Pohick church in Virginia. By all accounts at the time, he was rather devout.
He seemed to believe in an afterlife, and also that God had a hand in the affairs of the world, guiding events and putting everything that happened up to this godly Providence. He also believed that this same providence came into play when it came to the creation of the United States.
But it doesn't necessarily say he was a serious Christian. Of all the private correspondence we have that Washington was involved in, he never mentioned Jesus, and rarely mentioned him in non-private papers.
He was a humanitarian, by all accounts, believing in charity and helping the poor. He came right out and said it, in fact.
Let the Hospitality of the House, with respect to the poor, be kept up...I have no objection to your giving my Money to Charity...when you think it is well bestowed. What I mean, by having no objection, is, that it is my desire that it should be done.
More importantly, he accepted that there are other religions, and their right to exist. When he wrote to the Hebrew Congregation in Rhode Island, he said,
For happily the government of the United states, which gives to bigotry no sanction, to persecution no assistance, requires only that they who live under its protection should demean themselves as good citizens... May the children of the stock of Abraham, who dwell in this land, continue to merit and enjoy the goodwill of the other inhabitants.
Washington, in the end, while personally religious still signed a Constitution that guaranteed the free expression of religion while at the same time making it quite clear that no religion would rule the country.
John Adams we have already discussed. He believed that we are not a Christian nation.
Thomas Jefferson
Thomas Jefferson is an interesting person when it comes to religion. He didn't say much about it publicly, tended to agree that there was an afterlife, believed that God had an active guiding hand where humans are concerned and generally agreed with the moral aspects of Christianity. People often say he was Unitarian, but I'm not so sure about that.
He did say that Jesus' teachings were "the most sublime and benevolent code of morals which has ever been offered to a man," but he also worked against financial support of churches by the state, and yes, it's Thomas Jefferson who gave us the phrase, "...wall of separation between church and state."
Some people actually came out against him, saying he wasn't fit to be in office because his religious beliefs were unusual. He always referred to himself as a Christian, but also qualified that by saying he was "a sect by myself," or a "Unitarian by myself."
Yet despite that he didn't believe in the "Holy Trinity." And even more importantly, he helped to write a Constitution which expressly forbade the formation of a State religion. Ensuring, once again, that we are not and were not a "Christian Nation."
Finally, Bishop Meade, who knew all of the "Founding Fathers" and apparently knew them well, when mentioning Jefferson's religious beliefs, referred to it as "disbelief."
James Madison
Madison is interesting in that he was a devout Christian, even going so far as to support funding of churches, support religious holidays, and really wanted all public servants to declare, publicly, their own Christian beliefs.
And yet, when it came to the country, he wanted the First Amendment to be worded somewhat differently. His proposal for the First Amendment was that it read:
The civil rights of none shall be abridged on account of religious belief of worship, nor shall any national religion be established.
He also backed off, later in life when he was more tempered and seasoned, of some of his more in-your-face religious stances. Writing in his later days, Madison backtracked on some of the things he supported, even going so far as to say that things like paid chaplains and the issuance of prayer proclamations by the President were unconstitutional.
I'm not sure what happened to Madison in his later days, but he wrote a lot that came as a complete 180 from his earlier days, arguing against public expressions of religion and opposing many of the things he had said earlier in his life.
Regardless of the reason, even the earlier Madison recognized that the country wasn't and would not be a "Christian nation."
Congress should not establish a religion, and enforce the legal observation of it by law, nor compel men to worship God in any Manner contrary to their conscience. - James Madison, 1811
Alexander Hamilton
And here, we find a deviation from most of his contemporaries. Alexander Hamilton was pretty big on religion - the Christian one, especially.
He believed it was impossible for "national morality" to "prevail in exclusion of religious principle."
And yet he still signed the document that expressly forbade the creation of an official state religion.
James Monroe
James Monroe remains an enigma when it comes to religion. Monroe's religious convictions are harder to pin down than the other Founding Fathers, because he himself burned a lot of his personal correspondence after his wife died.
The extant papers we do have from Monroe, be they personal or professional, are devoid of references to religion - even letters that he wrote to friends and family following the deaths of his son and wife (both of which devastated him).
He did have three bibles in his library, but nobody knows whether or not he ever cracked them open.
The same Bishop Meade who referred to Jefferson's religious views as "disbelief" wrote in memoirs about the men he knew, and while he talked about Washington, Madison and Jefferson, he did discuss their beliefs. But whenever he mentions James Monroe (five times) he is silent on religion.
We can't know, because of a distinct lack of information on the subject, about Monroe's religious views - because unless they were in the letters he burned, he never gave them.
The only thing we know for sure is that he was known to have attended Episcopal church at some point, had an Episcopal wedding and an Episcopal funeral.
It is so unusual that anyone during this time should be utterly silent on religion that I think it possible that of all of our Founding Fathers, Monroe may have been the one that was an atheist. But it's likely we'll never know for sure.
And he is the only one of the "Founding Fathers" who did not sign the Constitution - but not because of religion. He didn't like the fact that they omitted a Bill of Rights, wanted the people to directly elect the President and not have all this electoral college nonsense, and he had concerns that the Senate had way too much power. These were major sticking points for him, so he refused to sign.
Benjamin Franklin
Finally, Franklin. Our favorite eccentric. The Founding Father who used to like to sit naked and take an "air bath." Inventor, scholar, thinker. Franklin tended to succeed in just about everything he turned his hand to.
And he was a self-described Deist. He thought that there had to be a higher power, but he didn't think there was some omniscient God.
What he didn't do, however, was show contempt for religion. If people invited him to go to church with them, he went (whether or not he'd make it through the whole service, however, was another matter).
He came up with his "Thirteen Virtues," not in opposition to but instead of the Ten Commandments. Essentially, how to behave in society. And he didn't believe that you needed religion in order to live a moral and ethical life.
Franklin's view of the world was that science and its progress shouldn't be hindered by religion, and he practices what he, for want of a better word, preached.
At 84 years old, a few weeks before his death, he laid out his religious position in a letter to Ezra Stiles, 7th president of Yale College:
You desire to know something of my religion. It is the first time I have been questioned upon it. But I cannot take your curiosity amiss, and shall endeavor in a few words to gratify it.
Here is my creed.
I believe in one God, the creator of the universe.
That he governs by his providence.
That he ought to be worshipped.
That the most acceptable service we render to him is doing good to his other children.
That the soul of man is immortal, and will be treated with justice in another life respecting its conduct in this.
These I take to be the fundamental points in all sound religion, and I regard them as you do in whatever sect I meet with them.
As to Jesus of Nazareth, my opinion of whom you particularly desire,
I think his system of morals and his religion, as he left them to us, the best the world ever saw or is likely to see; but I apprehend it has received various corrupting changes, and I have, with most of the present dissenters in England, some doubts as to his divinity;
though it is a question I do not dogmatize upon, having never studied it, and think it needless to busy myself with it now, when I expect soon an opportunity of knowing the truth with less trouble.
I see no harm, however, in its being believed, if that belief has the good consequences, as probably it has, of making his doctrines more respected and more observed;
especially as I do not perceive that the Supreme takes it amiss, by distinguishing the unbelievers in his government of the world with any peculiar marks of his displeasure.
He even made a motion during the Constitutional Convention to have a clergyman brought in to pray for them as they deliberated.
Yet, Jon Butler, Dean of the Graduate School of Arts & Sciences at Yale University and author of
Awash in a Sea of Faith: Christianizing the American People, wrote that:
Benjamin Franklin was even less religious than Washington and Jefferson. Franklin was an egotist. Franklin was someone who believed far more in himself than he could possibly have believed have believed in the divinity of Christ, which he didn't. He believed in such things as the transmigration of souls. That is that human, that humans came into being in another existence and he may have had occult beliefs...
But the most important part of this ridiculously long post, the crux of the argument, is that even though each of the Founding Fathers, as they are styled, may have had deep faith, a little faith or no faith, all of them believed that that faith should be kept out of the business of government.
And they all wished to ensure that the United States of America was not and would not be a "Christian nation," a "Muslim nation," a "Jewish nation" or any other religious nation. All but one of them put their signatures on the document which guarantees that.
Here endeth the lesson.