Fabiola's visit to Bethlehem had been shortened by the threatened invasion of the Huns which compelled Jerome and his friends to take refuge for a time on the seaboard of Palestine. Fabiola here took leave of her companions and set sail for Italy, but not until Jerome had completed this letter for her use (§22). It contains a mystical account of the vestments of the High Priest worked out with Jerome's usual ingenuity and learning. Similar treatises are ascribed to Tertullian and to Hosius bishop of Cordova, but these have long since perished. Its date is 396 or 397 a.d.