Was George Washington a deist or a Christian? It is an important question, as Washington was not only the first president but the most respected of all of America's founding fathers.
In their book, Washington's God, Michael and Jana Novak investigate Washington's public and private life to answer this question. The evidence is mixed:
Toward the view that Washington was a deist: Washington rarely referred to Jesus Christ (although he did write a letter to the Delaware Indians and recommend the religion of Jesus Christ), but instead he preferred the term "Providence," or generic terms like "the Author of our Blessed Religion." Washington regularly refused to take communion at church. When asked point-blank if he believed in Jesus Christ, he would not answer the question. When he died, he did not ask for a minister, and simply said, "'Tis well."
Toward the view that Washington was a Christian: Washington was a member of the Anglican church, which he attended regularly, including overseeing business of his local church. He agreed to be godfather to eight children, something the less religious Thomas Jefferson refused to do. He spoke of "Providence" in Christian terms, not deist terms. A deist believes God is like a watchmaker who makes the world and then is not involved; Washington instead spoke of divine Providence intervening and bringing together the events that led to his victory in the American Revolution. His reluctance to explicitly state his faith in Jesus Christ can be understood as typical for an Anglican who is more reserved about public expressions of faith. Nevertheless, there are reports of him privately praying during the war, and he insisted on having chaplains in the Continental Army. After his death, Martha Washington spoke of it as a Christian death.
On balance, Novak concludes that while he was very private about his faith, George Washington was, indeed, a Christian. He notes that Washington believed in religious liberty and opposed a state church, but Washington supported an accomodationist view of church and state that allows for public expresssions of general faith in the public square, without an endorsement of any particular denomination.