On this day the Church urges us to gladness in the middle of this time of expectation and penance: the coming of Jesus approaches more and more. St. John, the holy precursor, announces to the Jews the coming of the Saviour. 'The Saviour," he says to them "lives already among us, though unknown. He will soon appear openly." Now is the time for fervent prayers and for imploring Jesus to remain with us by His mercy. Let us prepare the way for Him by repentance and penance and by a worthy reception of the Sacraments. All the prayers of this Mass are filled with what the Church wishes our souls to possess at the approach of the Saviour.
(The Roman Missal, 1962)
Today is Gaudete Sunday. The first words of the Introit at today's Mass are "Gaudete in Domino semper!" Rejoice in the Lord always! Today we light the pink candle of our Advent wreath, and the priest wears rose or pink vestments at Mass, to symbolize the joy we feel as Christ's arrival nears.
The Lord will come, and will not tarry, and will bring to light the hidden things of darkness, and will manifest Himself to all the nations, alleluia. Vespers Antiphon 1 (1 Cor. 4, 5)