Christian art began as a language of symbols, the Good Shepherd, fish, anchor, birds, and the cross, served as a kind of hieroglyphic writing, opening the history of Christian art. Art was forced to go underground, literally, via the Catacombs. This era was called the Period of Persecution and lasted from 1 - 313 AD. The Catacombs served as an underground cemetery as well as a church for services and secreting Christians fugitives.
The history of Christian painting may perhaps be conceived as a great compromise with Hellenism. With the collapse of the classical world, the most subtly refined civilization that the world has ever seen came to an end. By its spiritual tendencies and its denial of the earthly, Christianity placed almost insuperable barriers to art. "Great Pan was Dead"
Religion with the Greeks had been a joyous cult of the senses teaching men to enjoy life in the here and now; it now became a belief in the other world, which regarded earthly existence as only a sad preparation for the life to come. True, the spring still came; men loved, the flowers bloomed, the birds sang, and the meadows were green. But all this was a delusion of Hell intended to lead the believer astray and to fill his soul with sinful thoughts. The world beyond his home, the present world only a Golgotha, where the skull lay and Christ hung crucified.