John Sawyer ( The Fifth Gospel: Isaiah in the History of Christianity ) summarizes the uses that Christians have made of the “ox and ass” of Isaiah 1:3: “Some commentators like Gregory of Nazianzus . . . interpret the ox as a symbol of the Jews and the ass as the gentiles loaded with the sins of idolatry, so that Isaiah’s prophecy implies that all humanity will be free when the Messiah comes.  Others, including Origen and Jerome, found in the invidious, taunting contrast between dumb animals who recognize their master in the manger, and Israel who ‘does not know, my people do not understand,’ a proof-text about the blindness and obduracy of the Jews who reject Christ.”  Jerome also links 1:3 to Isaiah 32:20, which envisions ox and ass roaming free in a restored land.  He notes the prohibition of mixing ox and ass in Deuteronomy 22:10, and “concludes that in the new age people will no longer be bound by the law, a further argument for the rejection of the Jews and Judaism.”

In Christian art, the ox is often depicted as respectful toward the Christ in the manger, while the ass is distracted and “embodied materialism and the inability to appreciate the miracle of Christ’s birth.”