I remember as a child hearing an evangelical Anglican remark during my that calling Mary ‘Mother of God’ was terrible. There were people during the early fifth century who thought similarly. One of them may or may not have been Nestorius, the Archbishop of Constantinople.
Whatever Nestorius himself believed, the name `Nestorianism‘ came to be used for the view that so stressed the separateness of Christ’s humanity and hid divinity as to lose sight of their unity. This belief manifested itself in a refusal to use the title ‘Mother of God’ of our Lady, ‘Mother of Christ’ being one proposed compromise. In opposing this view the Council of Ephesus in 431 declared Mary to be the Mother of God. Christ, although both human and divine, is one person. That person is God the Son, and so Mary is appropriately called Mother of God. She is not, for sure, Mother of God as God. Rather she is Mother of God as man. To deny this is, in effect, to deny the Incarnation. This man is God. That baby was God.
This title for Mary points to an important truth about Jesus. Those, like no doubt that Anglican minister from my youth, who think that in talking about Mary we detract from Jesus are exactly wrong. In fact, it is both interesting and important that in order to talk about Christ, the Church talked about Mary. God became a human being, a member of an animal species, and a member of a family and numerous communities. He was not some kind of divine Robinson Crusoe; he was and is a social being. And so in talking about him we naturally talk about those whose lives he touched and those who influenced him – supremely Mary, from whom he took his very humanity. It is the same with all of us. Pick up any biography, and the chances are that the early chapters will dwell on its subject’s family.
Today’s feast reminds us of the communal nature of humanity, and in a sense of the Church, present in microcosm in Christ’s family. The saving events of Jesus’ life involved people other than Jesus, as do each of our participations in those events.