The commentaries on Martianus Capella’s De nuptiis Mercurii et Philologiae and Vergil’s first six books of the Aeneid, which represent typically medieval allegoric interpretations of two ancient texts of high importance for scholarly formation in medieval Western Europe, are obviously written by the same author to be used in cathedral schools of the twelfth century in order to demonstrate the unity of what he calls philosophy, which comprises both knowledge of the universe and ethics. The author composed his commentary on Vergil, as can be shown by an analysis of quotations, only after that on Martianus, with anagogic intention: the destination of man, that is to say of the microcosmus, according to his conviction, aims at surpassing the material world, the macrocosmus, the understanding of which is provided by the Liberal Arts, their knowledge granting the ascension to the sphere of eternity. This is why the commentary on the Aeneid, like the interpretation given by John of Salisbury, ends within the sixth book, where Aeneas, during his visit to the underworld, arrives at the Elysium, the region, where the blessed dwell. This arrangement of the commentaries points to the Cosmographia of Bernardus Silvestris, the first part of which deals with the creation of the universe, whereas its second part concentrates on the creation of man, according to the sequence in the relative report in the Biblical Book of Genesis. Thus it is not improbable, that Bernardus Silvestris is really the author of both commentaries.