In a flirtatious letter to Madame Brillon de Jouy, née Anne-Louise Boivin d'Hardancourt (March 10, 1777), Franklin states there are actually 12, not 10 Commandments.
People commonly speak of Ten Commandments. I have been taught that there are twelve. The first was increase & multiply & replenish the earth. The twelfth is, A new Commandment I give unto you, that you love one another. It seems to me that they are a little misplaced, And that the last should have been the first.Chris Rodda's "Liars for Jesus" (Volume I) also references this quotation on page 423. She notes that Christian Nationalists who look for and cherry pick quotations to fit their narrative don't use this one.
Interestingly, I also found in Rodda's chapter on Franklin (11 in her book) a letter that deals with the Deism controversy. Franklin admitted that he was a "thorough Deist" when younger but soon abandoned that creed. In 1728, in his early 20s, Franklin thought the God of the Universe was a Deistic, impersonal Creator who created a personal God that rules our solar system, one he would worship.
By the end of his life, I doubt Franklin continued to believe this. Where he ended up was belief in an active personal God but without endorsing any orthodox doctrine. Rather, the doctrine he did endorse was morality and doing good to our fellow man as the central purpose of all valid religions. And that Jesus -- about whose divinity Franklin had "doubts" -- was the greatest moral teacher.
Franklin had a friendship with the evangelical preacher George Whitefield. Whitefield tried and failed to convert Franklin to his creed. Rodda uncovers a letter from Franklin to Whitefield (Sept. 2, 1769) where, aged 63 at the time, Franklin addressing the doctrine of Providence, again, sounds like some kind of Deist:
I see with you that our affairs are not well managed by our rulers here below; I wish I could believe with you, that they are well attended to by those above; I rather suspect, from certain circumstances, that though the general government of the universe is well administered, our particular little affairs are perhaps below notice, and left to take the chance of human prudence or imprudence, as either may happen to be uppermost. It is, however, an uncomfortable thought, and I leave it.Well America won the then brewing revolutionary war that was the subject of Franklin's 1769 letter to Whitefield. Franklin's speech as an old man at the Constitutional Convention reveals belief in a Providence who more actively personally intervenes in man's affairs.