This has always been the true belief of Christians. Against those who denied it, the Council of Ephesus proclaimed that 'if anyone should deny that the Emmanuel is truly God, and that therefore the most Blessed Virgin is the Mother of God, since she gave birth according to the flesh to the incarnate Word of God, let him be anathema'.
The Blessed Trinity, in choosing Mary as the Mother of Christ, a Man like us, has brought each one of us under the shelter of her maternal cloak. She is the Mother of God and our Mother.
The divine Motherhood of Mary is the source of all the perfections and privileges with which she is endowed. Because of it, she was conceived immaculate and is full of grace; because of it, she is ever virgin, she was taken up body and soul to heaven and has been crowned Queen of all creation, above the angels and saints. Greater than she, none but God. 'The Blessed Virgin from the fact that she is the Mother of God has a certain infinite dignity which comes from the infinite good, which is God.' There is no danger of exaggerating. We can never hope to fathom this inexpressible mystery; nor will we ever be able to give sufficient thanks to our Mother for bringing us into such intimacy with the Blessed Trinity.
We were sinners and enemies of God. Redemption has not only freed us from sin and reconciled us with Our Lord. It has also made us into children of God and has given us a Mother, the very Mother who gave birth to the Word when he took human nature. Could there ever be a greater, more generous, outpouring of love? (Friends of God, 275-275)