Photo by Scala/Art Resource, NY

A pure fish and a holy shepherd—two of the images of Avercius’s poem—are common themes in the earliest Christian art, which began to appear in Roman catacombs between about 175 and 200 C.E., around the time the poem was written. The detail of fish and loaves, shown here, is painted on the walls of the catacomb of Callistus (compare with photo of Good Shepherd painting from the catacomb of Priscilla).

Both images may be interpreted in diverse ways: Depending on the context, the fish could illustrate a popular meal, a ritual sacrifice in Greco-Roman tradition or the Eucharist; the shepherd might represent a pastoral theme, a pagan deity or the Christian Good Shepherd. According to Laurence H. Kant, the emerging Christian community designed its new public funerary monuments and art so that fellow Christians could understand their fuller meaning while outsiders were left to make their own, more limited interpretations..