Because we are so used to the Incarnation, of the child who came to live among us and the manner in which it happened, I think we take for granted its inevitability. It was not necessary. God could have redeemed humanity in some other way with more might, more power, more fireworks - think Hollywood action film, but on a cosmic scale. God could simply wipe out humanity’s sin, just like that. He could have done that, or in any other way you might imagine, he could have done that.
He could also have sent his son, but not as an Infant, so weak, dependent and vulnerable, just like any other child subject to the vicissitudes of human living. He could have done it some other way. But this was the way that was best for us: that he come as an infant, a baby. This was the way that St. Anselm and St. Thomas Aquinas suggest was the best for humanity, for it indicated to us that God was not so great or transcendent that he would not deign to come to us. It shows us that our human nature, however much it troubles and haunts us, is worthy of redemption and good, for God took on this very nature. It shows us that God loves us as whole human beings, in the flesh, in need of development and love to reach our potential, and so he took on human nature. He is Emmanuel, God with us (Isaiah 7:14; Matthew 1:23), and he is the child Jesus.
John W. Martens
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