Chi Rho
In the Catacombs of Rome, artists indirectly hinted at the resurrection by using images from the Old Testament such as the fiery furnace and Daniel in the Lion's den. Depictions prior to the 7th century generally showed secondary events such as the Myrrhbearers at the tomb of Jesus to convey the concept of the resurrection. An early symbol of the resurrection was the wreathed Chi Rho (Greek letters representing the word "Khristos" or "Christ"), whose origin traces to the victory of emperor Constantine I at the Battle of the Milvian Bridge in 312, which he attributed to the use of a cross on the shields of his soldiers. Constantine used the Chi Rho on his standard and his coins showed a labarum with the Chi Rho killing a serpent.