December 25th is the feast of the Nativity of Our Lord and Savior Jesus Christ, the greatest Christian holy day after Easter. “Christ Mass” is the Eucharistic feast celebrating the birth of Christ, the Incarnation of Second Person of the Holy Trinity in the womb of the Virgin Mary, who came to suffer and die on a cross to save us from our sins. Three Masses are celebrated at Christmas: Midnight Mass, or "The Angel's Mass"; Mass at Dawn, or "The Shepherd's Mass; and Mass during the Day, or "The King's Mass." The octave of Christmas lasts from December 25th until January 1st, the Solemnity of Mary, the Mother of God. In the current Roman Catholic calendar the Christmas season continues until the feast of Jesus' baptism on the Sunday following Epiphany; on the ancient liturgical calendar Christmastide continues until Candlemas, or the Presentation of Jesus on February 2nd. Christmas is a Holy Day of Obligation.