This 4th-century mosaic in the church of Santa Pudenziana in Rome is part of the apse mosaics which are the earliest figural representations to survive in a church in Rome.
St Mark, whose feast is today, 25 April, is commonly depicted as one of the four beasts who worship around the throne of God. In the case of this evangelist, it is as a winged lion.
The lion derives from Mark's description of John the Baptist as a "voice of one crying out in the desert" (Mark 1:3), which artists compared to a roaring lion.
Uploaded by Lawrence OP on 25 Apr 08, 3.33AM CDT.