1. It praises Washington as Christian in the context of crediting Providence for the American victory. Washington's response is devoid of explicitly Christian language, though it does say:
The man must be bad indeed who can look upon the events of the American Revolution without feeling the warmest gratitude towards the great Author of the Universe whose divine interposition was so frequently manifested in our behalf....2. It harshly criticizes one General Lee (Richard Henry Lee?).
As soon as I was honored with an acquaintance with you at Cambridge, upon your arrival at my house with your Suite, I was ready to look up to heaven, & say, “Blessed be God; who hath given us a General who will not rashly throw away the lives of his Soldiers, or hazard the fate of his Country unnecessarily upon a single Battle, but will proceed with all wisdom & caution”! I plainly saw, even the very first day, that General Lee was disappointed, & affected to turn the eyes of the army upon himself. But how happy was it for the country, that a man void of all principles, both religious & moral, notwithstanding all his military accomplishments, was not entrusted with the chief command.3. Lastly, it invokes prophecy:
But I view what God hath done, not as if he had a partial regard for us, Who, like Israel, have shewed ourselves an unworthy people, by growing more regardless of his gospel in the enjoyment of the multitude of his mercies; but as tending to bring forward some grand revolutions in the civil & ecclesiastical polity of the nations, agreable to the Prophecies of the new Testament, which now approach to their fulfilment.Like his fellow orthodox colleague Ezra Stiles, Langdon was an enthusiastic supporter of the French Revolution. And like the heterodox unitarians Joseph Priestley and Richard Price, Langdon apparently prophesized that the success of the French Revolution would usher in some kind of global republican reforms in matters of religion and politics.
Langdon again wrote to Washington in 1791; though I don't think Washington responded to this letter (if he did, I couldn't find it). Langdon wrote:
If I have proved from that divine prophecy that we live in the very times precisely marked out for the beginning of surprizing Revolutions in the world, it may serve greatly to confirm the truth of the holy Scriptures; & the honours which divine Providence has conferred on you will afford double satisfaction.Langdon noted he enclosed another sermon which articulated his argument. It was probably the one entitled "Observations on the Revelation of Jesus Christ to St. John. Which Comprehend the Most Approved Sentiments of the Celebrated Mr. Mede, Mr. Lowman, Bishop Newton, and Other Noted Writers on This Book; and Cast Much Additional Light on the More Obscure Prophesies; Especially Those Which Point Out the Time of the Rise and Fall of Antichrist . . ." You can find large parts of it online from the embedded search.
This link in particular has generous portions. The zeitgeist about which I write and find fascinating demonstrates how Protestantism and Enlightenment categories (like the "deism" that is arguably inconsistent with Christianity) have blurred lines, hence the categorization of this spirit as some kind of hybrid of Protestantism and Enlightenment, Christianity and Deism.
Men like Thomas Jefferson, John Adams, Ben Franklin and ministers like Joseph Priestley and Richard Price took cover under the umbrella of "Protestant Christianity" while keeping their guard up against the "orthodox" who would deny them the "Christian" label. One area that drew together both wings of Protestantism was anti-Catholicism.
We see that evident in Langdon's sermon. 1. anti-Catholicism; in the context of 2. enthusiastic support for the French Revolution; and 3. a prophesying on the success of the FR where we would both see the taking down of the Catholic Church and a consequent universal establishment of republican politics and religion. (Paragraphs added by me for clarity.)
"The capital of the empire of Antichrist is repeatedly called Babylon in the Revelation. The name is figurative and mystical; Rome is the city really meant. * * * We are plainly informed in the 17th chapter what kings are to be employed in destroying the great harlot, the city and church of Rome; the very kings who at first agreed in one creed and gave their power to the beast. These kings will at length entirely change their minds and become the most zealous enemies to that ecclesiastical empire which they themselves had established. They will find out that Rome has caused insurrections against them and fomented rebellions and seditions; and that the religion they have promoted has drained away their wealth, encouraged and multiplied drones in society and impoverished and diminished their subjects.
In the execution of vengeance, the river of wealth, which was continually flowing through Rome and the church, will be dried up. Vast revenues which the Popes formerly received have been greatly diminished bv the Protestant Reformation. Moreover, when the church of Rome is no longer mixed with the civil polity of the kingdoms, her sources of strength as well as wealth will be cut off and the way prepared for her utter ruin. Likewise, the dissolution of the numerous orders of ecclesiastics in the several kingdoms, which have been the gates and bars of Rome, will leave her exposed to a sudden assault which may at once bring down all her power. Of this we have already seen some approaches in the total suppression of the order of Jesuits and the methods taken in several Roman Catholic kingdoms for the abolition of convents.
The banishment of the Jesuits, * * * with the suppression of convents, may naturally be considered among the things signified by the Sixth Vial. * * * The bishops of Rome had obtained a grant of supreme ecclesiastical jurisdiction over all the western churches, A. D. 379, and immediately began to exercise it. Of this jurisdiction the illustrious Sir Isaac Newton has produced abundant proof in his observations on the power of the eleventh horn of Daniel's fourth beast."Langdon also said:
The world is roused to a sense of civil and religious liberty by the spirit of America. France is searching the foundations of despotism and establishing on its ruins the freedom of a great nation; and God has given them a king; to be the restorer of liberty, and a second Washington to command their national troops. May we not look for events more and more remarkable until all the nations of Europe shake off the yoke of ecclesiastical tyranny and assert the rights of nations and of conscience?The above, again, was written in 1791.