The Arian Baptistery, c.500
The Catholic Baptistery c.430
I took both pictures; you can considerably enlarge them if you click on them.
Ravenna today is an unprepossessing town on the Adriatic coast of Northern Italy, but for a time it was the capital of the Western Roman Empire: the emperor Diocletian had decided no longer to subject himself to the unpredictable whims of the Roman mobs, and had established four capitals throughout the Empire; Italy was governed then from Milan. After a passage of time Ravenna, the little coastal town that had been founded, like Venice, on stilts in a lagoon, succeeded it and became the capital of what remained of the West. It had a port, founded by Augustus, called Classe, and so was handy for Byzantium and for getting troops in and out in a hurry. In later eras it became the Ostrogothic capital, and then the location of the Byzantine Exarchate. The Lombards had it until the Franks saw to them, and then Ravenna began its slow decline.
Its (presumably magnificent) civil buildings have all vanished now, but its most important religious structures survive, together with many of the mosaics that adorn them, in many cases as fresh and new as the day they were created.
The style clearly recalls to our minds the East, but in fact it is thought that they are some of the few survivors of Western mosaic art and iconography. That there should be similarities is not surprising, given that West and East were part of one world for so long.
The two examples I am posting today are the central motif in the domes of each of the two baptisteries in Ravenna, the first is is from the 'Arian' baptistery (the Goths were Arians for a long time), about 500, and the other is from the 'Neonian' (otherwise known as the Catholic or Orthodox) baptistery, built around 430.
Both show the same scene; our Lord's baptism. But I noticed subtle differences, and if I knew more about Arianism, I might be able to account for more than I can. Ideas, anyone?
1) The Catholic baptistery shows Christ bearded, the later Arian shows him beardless.
2) In the Arian mosaic, the Baptist simply lays his hand on our Lord's head while the Holy Spirit fountains the water. In the Catholic baptistery, John is really doing the baptizing.
3) Both also show a personification of the Jordan river; however, in the Arian baptistery, there seem to be horns on his head. Is this a reference to Moses (giving water from the rock who was Christ?). Elsewhere in the baptistery there is a depiction of what looks like an enthroned rock.
There are also some liturgical points that should not be missed:
1) I think we should also notice that in both cases the baptism is not by full immersion, as the common opinion would have us believe was the universal practice of the Church in the first centuries. It is clearly by affusion, pouring, as we do now in the West, the only difference being that the baptizatus is here standing in water. So let us have no more nonsense about full immersion being the 'proper' way to baptize.
2) In both cases, John is not standing in the water, but clearly outside the font/river. Only the candidate gets into the water. I have known several full-immersion fonts where the celebrant is required to get wet with the candidate.