The name “Theotokos” means “Mother of God” in Greek, a title officially recognized at the Council of Ephesus in 431 AD, but one which was in use well before this council. Nestorius proposed that she was in fact the Christotokos, a theology which divided His human and divine natures, and was hence unacceptable. He is, of course, one person with two natures, divine and human, united in one person. Mary, as the Mother of God, should be honored greatly, as she submitted wholly to the will of God, and should be an example of how to live our own lives. The Theotokos is greatly honored throughout the Divine Liturgy as well as in many other prayers, including Akathists, or hymns, that are entirely dedicated to her.
Theotokos is an ancient title for the Virgin Mary, which literally means “the Birthgiver of God” or “Mother of God.” This title for the Virgin Mary has been in use by the Church from time immemorial. When it was officially recognized at the Council of Ephesus in 431 AD, it was universally known.
But why honor Mary at all? We honor her because she points us to Christ, as an example of complete submission to God. In an age where we idolize actors, generals, musicians, and other famous people, we should instead turn our focus on to the saints, who by their example show us what faith in Christ can mean for our life. For this reason we honor the Virgin Mary and other saints; and to protect the unity of Christ, we call His mother Theotokos.