On Lincoln, Jefferson, Andrew Johnson, and Hayes:
Two of the most famous presidents in American history had no formal religious affiliation. The first, Thomas Jefferson, lost his faith in orthodox Christianity at an early age, but continued to believe in an impersonal God as the creator of the universe. Jefferson famously edited the New Testament by removing references to the miracles and leaving in Jesus’ teachings.
The second, Abraham Lincoln, was raised in a religious household and spoke frequently about God (particularly as president), but never joined a church. Scholars have long debated Lincoln’s beliefs, including the question of whether or not he was a Christian, and some aspects of his faith remain a mystery.
Lincoln is not the only president for whom there is some uncertainty surrounding his affiliation and beliefs. Some presidents were more private than others about their religious leanings and some may have evolved in their beliefs during their life.
For example, Lincoln’s second vice president and ultimately his successor, Andrew Johnson, identified himself as a Christian, but never was formally part of a denomination or congregation. Another 19th century president, Rutherford B. Hayes, sometimes attended Methodist churches, but “moved among Protestant denominations during his life,” according to the Berkley Center for Religion, Peace & World Affairs at Georgetown University.