“[T]he manger makes us think of the animals that find their food there. Here, in the Gospel, there is no mention of animals; but the meditation, guided by faith, reading the Old and the New Testaments in correlation to each other, did not take long to fill up this lacuna, reporting itself to Isaiah 1,3: «The ox knoweth his owner, and the ass his master’s crib: but Israel hath not known me, and my people hath not understood»
Iconographic tradition has theologically interpreted the manger and the swaddling cloths in terms of the theology of the Fathers (…) So the manger has in some sense become the Ark of the Covenant, in which God is mysteriously hidden among men, and before which the time has come for “ox and ass”—humanity made up of Jews and Gentiles—to acknowledge God.
Therefore (…) we have two animals as representation of mankind, by itself devoid of understanding and that, before the Child, before the humble apparition of God in the stable, reaches knowledge and, in the poverty of such birth, receives the epiphany that allows everyone to see. Soon enough, Christian iconography individuated this meaning. No nativity scene will give up its ox and donkey”
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