The literary fame of Avitus rests on his many surviving letters (his recent editors make them ninety-six in all) and on a long poem, "Poematum de Mosaicae historiae gestis" (also known as "De spiritualis historiae gestis"), in classical hexameters, in five books, dealing with the Biblical themes of original sin, expulsion from Paradise, the Deluge, and the Crossing of the Red Sea. The first three books offer a certain dramatic unity; in them are told the preliminaries of the great disaster, the catastrophe itself, and the consequences. The fourth and fifth books deal with the Deluge and the Crossing of the Red Sea as symbols of baptism. Avitus deals freely and familiarly with the Scriptural events, and exhibits well their beauty, sequence, and significance. He is one of the last masters of the art of rhetoric as taught in the schools of Gaul in the 4th and 5th centuries. His poetic diction, though abounding in archaisms and rhythmic redundancy, is pure and select, and the laws of metre are well observed. Writing in the "Catholic Encyclopedia", Thomas Joseph Shahan says "that Milton made use of his paraphrase of Scripture in writing "Paradise Lost"." Avitus also wrote a poem for his sister Fuscina, a nun, "De consolatoriâ castitatis laude".