He assisted his brother in the discharge of his functions, and Sidonius Apollinaris describes him as directing the psalm-singing of the chanters, who were formed into groups and chanted alternate verses, whilst the bishop was at the altar celebrating the sacred mysteries.
In the same epigram, which constitutes the epitaph of Claudianus Mamertus, Sidonius also informs us that this distinguished scholar composed a lectionary, that is, a collection of readings from the Christians' scriptures to be made on the occasion of certain celebrations during the year.
Written between 468 and 472, this work was destined to combat the ideas of Faustus, Bishop of Reii (modern Riez, in the department of Basses-Alpes), particularly his thesis on the corporeity of the soul.
Claudianus studied the works of Apuleius, and, in a letter to rhetorician Sapaudus of Vienne, recommended Nævius, Plautus, Varro, and Gracchus as stylistic models.
The logical method pursued by Claudianus commanded the esteem and investigation of Berengarius of Tours, Nicholas of Clairvaux, secretary to Saint Bernard, and Richard de Fournival.