This text is from a special arrangement of the Psalms. Several Church Fathers made their own groupings for the Scriptures. Of these so-called 'cahins' the most famous is that of St. Thomas Aquinas. The author of the arrangement represented by this leaf is unknown. The scribe of the XIIth century often came close to achieving perfection. The symmetry of his letters, the unerring accuracy of his practised hand, and his ideals for letter forms have rarely been equaled and have never been surpassed. The words which were inserted in the margin are not corrections but were added as guides to the content of the page.