Bart Ehrman, The New Testament: A Historical Introduction to the Early Christian Writings, sixth edition (Oxford University Press, 2016), 5.
If we turn the clock back 1,850 years to the middle of the second century, we find people calling themselves Christian who subscribe to beliefs that no modern eyes has seen or ear heard; Christians who believe that there are 2 different gods, or 30, or 365; Christians who claim that the Old Testament is an evil book inspired by an evil deity; Christians who say that God did not create the world and has never had any involvement with it; Christians who maintain that Jesus did not have a human body, or that he did not have a human soul, or that he was never born, or that he never died.
The Amateur Exegete 