Rejecting the divinity of Christ in the early 1860s, Amberley wrote on his 21st birthday, "I am therefore at the present moment what is called a 'Deist'." In 1864, he embarked on a comparative study of religions and started writing "An Analysis of Religious Belief". He published the first part of an article on "The Church of England as a Religious Body" in December 1866 and the second in February 1867, arguing that the clergy should consider all theological doctrines equally because the Church of England was a national church and tithes were paid by all citizens, regardless of their personal convictions.