The Hospitality of Abraham
Basilica of Santa Maria Maggiore, Rome
The mosaic illustrates Genesis 18:1-15. On the left in the lower register, Abraham has Sarah bake loaves for the visitors. On the right, he brings them a roasted calf. The background for the figure of Abraham and Sarah is relatively naturalistic, whereas the ground behind the visitors is all gold, emphasizing their heavenly origin.
The liturgical character of the calf is suggested by the parallel phrasing between Genesis 18:7, where Abraham ad armentum cucurrit, et tulit inde vitulum tenerrimum et optimum ("ran to the herd and took a tender and perfect calf") and Leviticus 9:2, where Moses tells Aaron tolle de armento vitulum pro peccato et arietem in holocaustum utrumque inmaculatos et offer illos coram Domino ("take from the herd a calf as a sin offering and a goat as a holocaust, each immaculate, and offer them to the Lord").
Liturgy is further suggested by the structure behind Sarah. In 18:1 it is simply a tabernaculum or "tent." But the mosaic presents it so as to remind the viewer of both a Christian church and the Jerusalem Temple. Like the Temple in the basilica's apsidal arch a few feet away, the structure has a roof of tuft-like tiles and a pair of tied-back curtains at the door. But like a church, it has a cross in the pediment.
At the feet of the three visitors, beneath the table, is the basin of water that Abraham provided so they could wash their feet .
As for the upper register, in an earlier commentary I proposed that it portrayed Genesis 18:2, where Abraham saw the three men and "ran to meet them from the door of his tent, and adored down to the ground." Abraham's bent-over posture would be consistent with that verse, and in most mosaics in this series the upper register does precede the lower chronologically. But on further consideration I think it is possible that the scene represents Genesis 18:10, where Abraham is told Sara will have a son. The visitor in the center is gesturing toward Abraham as if making a statement. Further, that statement is made in the first person singular, "I will return and come to thee at this time…and Sara thy wife shall have a son." The switch to the singular would suggest that the speaker is more important than the other two, a consideration suggested by the mandorla behind him.
The early exegetes differed regarding what was represented by the three visitors. Some suggested, and later images assumed, that they signify the Trinity. Others saw them as simply "the Lord" accompanied by two other beings variously identified.1 Our mosaicist seems to be in the latter school, giving a mandorla to only one of the visitors in the upper register and in the lower one making him slightly taller than the others and placing the basin at his feet specifically.
This mosaic is part of the extensive series of Old Testament scenes portrayed in mosaics along the two walls of the nave. To view the others, follow this link.
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Read more about images of the Trinity and about Abraham.
Photographed at the basilica by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.
1 See the quotations in Glossa Ordinaria I, 230-31: All quoted authors assume it is God who is visiting, except for Augustine, who insists the three were simply angels. For the Greek glossa the three visitors prefigure Christ's Transfiguration with Moses and Elijah. Ambrose and Cyril of Alexandria take the three as a sign of the Trinity.