«IESU REDEMPTOR OMNIUM». – Hymn of Lauds in the Common Office of the Popes and Confessors, in which the merits of the Saint whose feast is being celebrated are extolled in a general manner. It is of unknown authorship and dates to around the 10th century.
The fundamental theme is the contempt for earthly goods in order to attain eternal life. Notable is the scarcity of colour and movement.
«IESU REDEMPTOR OMNIUM - QUEM LUCIS». – This is the hymn for Vespers and Matins on the feast of Christmas, of unknown authorship, dating to the beginning of the 10th century.
The birth of Jesus ab aeterno, the theme on which it chiefly dwells, makes it clear that the hymn was composed during the Arian controversy. Begotten by the Father from eternity, come into the world of a virgin, He is reborn spiritually in every man. These three births are greeted with a new song by the entire universe.