Aquinas wrote commentaries on five Old Testament books - Psalms, Job, Isaiah, Jeremiah, Lamentations; on two Gospels - Matthew and John; and on the Pauline epistles - Romans, I and II Corinthians, Galatians, Ephesians, Philippians, Colossians, I and II Thessalonians, I and II Timothy, Titus, Philemon, and Hebrews. The early catalogues of Aquinas's works also list a commentary on the Song of Songs, but no such commentary has been found. In addition, there are two inaugural lectures [principia) that are discussions of scriptural texts. The first inaugural lecture is based on a verse from Psalm 103: “ Watering the earth from above”; the second focuses on a division of the books of Scripture. Weisheipl argues that both these lectures were given in connection with Aquinas's inception as Master of Theology at Paris in 1256. Finally, Aquinas composed a continuous gloss on all four Gospels, the Catena aurea (Golden Chain). It consists in a compilation of relevant passages from the writings of the Greek and Latin Fathers of the Church.