Summary of comments of this office by Dom Schuster, in his work L'année liturgique.

2nd Sunday after the Epiphany

The Introït antiphon is taken from psalm 65, inviting the whole world to adore the Lord and to sing psalms to his name.

The Gradual comes from psalm 106. The Lord sent his Word to heal the world, and for this reason a canticle of gratitude rises up from the hearts of all.

In the Alleluia verse - which, originally, was probably a simple acclamation following the reading of the Gospel - the angels and the virtues are invited to praise God (Ps. 148).

The Offertory of this day is also a jubilus taken from psalm 65. The prophet invites the universe to praise God and wants all men to know the benefits they have received from him.

The Communion antiphon, telling of the miracle of the conversion of water into wine and the subsequent admiration of the steward, explains the full meaning of the prodigy by making reference to the Holy Eucharist.

3rd Sunday after the Epiphany

As for all the Sundays of the cycle, the Introït inspires a holy joy and gratitude towards God. It takes the antiphon from Psalm 96.

The Gradual-responsory is taken from Psalm 101. "For the Lord hath built up Sion, and He shall be seen in His majesty."

The Alleluia verse belongs to Psalm 96, which is a veritable canticle of triumph for the inauguration of the new messianic kingdom, which is no longer of a nationalist character, as it was for Israël, but really universal.

The antiphone for the Offertory psalm is a canticle of triumph. "The right hand of the Lord hath wrought strength, the right hand of the Lord hath exalted me: Ishall not die, but live, and shall declare the works of the Lord."

This triple glorification of the right hand of God, found literally in Psalm 117, is an allusion to the mystery of the majestic Trinity. It is used also by the Church for the Mass of the Invention of the Holy Cross.

The Communion antiphon is taken from Saint Luke (IV : 22): "They all wondered at these things, which proceeded from the mouth of God". Now this chant is out of place, since it is no longer connected to the Gospel about Jesus'discourse in the Synagogue of Nazareth, which was originally assigned to to the 4th or 6th ferial day after the Theophania.

Fourth Sunday after the Epiphany and the following Sundays

The Sunday Masses after the 3rd Sunday and up to Septuagesima Sunday do not have any special chant assigned to them. The chants used are those from the 3rd Sunday. The reason for this anomaly is the uncertainty that dominates this last part of the cycle after the Epiphany. Everything depended upon the beginning of the Lenten fast; but in several Roman lectionaries, this cycle numbered up to ten weeks, whereas in others there are no more than three. The same was true for the Sundays after Pentecost. So we may reasonably think that, in the absence of particular chants for these additional Sundays, the Gregorian redaction of the antiphonary really reflects the usage of the 7th century.