If Mary isn't the Mother of God, then Jesus isn't who He says He is.

So, Jesus is God, yes? Most of us can agree on that much. And we know that Mary is the mother of Jesus.

Therefore, logically speaking, Mary is the Mother of God.

Mary was first defined as the Mother of God (Theotokos!) at the Council of Ephesus in 431 AD. This belief was a conclusion based upon belief in Jesus' Incarnation- that He is fully God AND fully man.

The Catechism of the Catholic Church states:

"the One whom she conceived as man by the Holy Spirit, who truly became her Son according to the flesh, was none other than the Father's eternal Son, the second person of the Holy Trinity. Hence the Church confesses that Mary is truly 'Mother of God' (Theotokos)." (CCC 495)

Mary is not the source of the divine nature of Jesus, but of His human nature. Just as we wouldn't say, though, that a mother is the mother of her child's body and not her soul, we also wouldn't say that Mary is the mother of Jesus' human nature and not His divine nature- both make Him who He is. (Example from Catholic Answers!!)

To separate Mary from Jesus is to deny that Christ is fully God AND fully man- a fundamental aspect of Christian Theology.

If Mary is not the Mother of God, then:

a) Jesus is not God, only man, and only has human nature (Arianism, rejected by the Church at the Council of Nicea in 325 AD)

b) Jesus is two separate persons- and Mary is only the Mother of the human person. (Nestorianism, rejected by the Church at the Council of Ephesus in 431 AD)

c) Jesus is only God and only seemed to have a human nature. (Docetism, rejected by the Church at the Council of Chalcedon in 451 AD)

To deny Mary as the Mother of God is to deny Christ's human and divine nature.

To deny Christ's nature is to deny either His humanity of divinity.

To deny His humanity or divinity means that no one can be saved.

This is catastrophic. If Mary is not the Mother of God, then death still has the final say.

So we praise God for His great gift of Mary in giving us her as Theotokos- God bearer- and we celebrate her in a special way on January 1st on the feast of Mary, Mother of God.

Still confused? Leave your questions in the comments!