On January 1st, the Catholic Church celebrates the Solemnity of Mary as the Mother of God.

History of Mary as the Mother of God

The title for Mary as the Mother of God (Theotokos in Greek) has early origins in Christianity. If Jesus is God and Mary is His mother, that makes her the Mother of God.

The Church saw objections to this theology in the 5th century, calling Jesus Christ’s divinity into question. In the early 400s, the bishop of Constantinople Nestorius began teaching that Jesus was not fully divine.

St. Cyril of Alexandria accused Nestorius of heresy to Pope St. Celestine. These tensions led to the famous Council of Ephesus in 431 that dogmatically confirmed Mary as the “Mother of God.” Along with honoring Mary, this Council confirmed that Jesus is in fact God.
 
Madonna of the Book by Sandro Botticellil
Madonna of the Book by Sandro Botticellil (1480)

Liturgical Origins of the Feast of Mary, the Mother of God

The earliest liturgical feast for Mary’s motherhood is the Feast of the Maternity of the Blessed Virgin Mary. Portugal first instituted this feast in 1751 to celebrate Mary as the Mother of God and it spread to other dioceses in the next two centuries.

In the calendar reform of 1969, the Catholic Church removed this feast and instituted a new universal one: Mary, the Mother of God on January 1st. Today, the Church celebrates it as a solemnity. In certain areas, it is a Holy Day of Obligation.

Why Celebrate Mary as the Mother of God?

Celebrating Mary as the Mother of God also commemorates the child Jesus, too. It’s fitting then that it comes on the eighth day of the Octave of Christmas.

Pope St. Paul VI writes:

This celebration, placed on January 1 …is meant to commemorate the part played by Mary in this mystery of salvation. It is meant also to exalt the singular dignity which this mystery brings to the “holy Mother…through whom we were found worthy to receive the Author of life.” It is likewise a fitting occasion for renewing adoration of the newborn Prince of Peace, for listening once more to the glad tidings of the angels (cf. Lk. 2:14), and for imploring from God, through the Queen of Peace, the supreme gift of peace.

God becoming man and saving us should already fill us with peace, joy and thanksgiving. But Jesus didn’t stop there: He also gave us His own loving mother to be our own mother as well.