He was probably a Unitarian so I don't know if you could consider hin a Christian. He is buried in the United First Parish Church (Unitarian) in Quincy, Massachusetts. It is possible that this church was still formally Congregational at the time of Adams. The final split between Unitarianism and Congregationalism took place about 1834. Fourteen of the Sixteen Congregational Churches in Boston, for instance, declared for Unitarianism at that time. What is interesting is that was almost the precise time when the Congregational Church was dis-established in Massachusetts.
