Psalms 6, 31, 37, 50, 101, 129, and 142 are the seven penitential psalms. These psalms were written by King David in remembrance of his sins and to ask God's forgiveness and are meditated on until this day for the same purpose. This commentary will assist those who wish to truly pray the penitential psalms rather than just reading them. We can consider that John Fisher became a saint in part by such holy considerations that went into preparing this series of seven sermons. May our reading his commentary help us also to become saints. St. Alphonsus writes: "a single bad book will be sufficient to cause the destruction of a monastery." Pope Pius XII wrote in 1947 at the beatification of Blessed Maria Goretti: "There rises to Our lips the cry of the Saviour: 'Woe to the world because of scandals!' (Matthew 18:7). Woe to those who consciously and deliberately spread corruption-in novels, newspapers, magazines, theaters, films, in a world of immodesty!" We at St. Pius X Press are calling for a crusade of good books. We want to restore 1,000 old Catholic books to the market. We ask for your assistance and prayers. This book is a photographic reprint of the original The original has been inspected and many imperfections in the existing copy have been corrected. At Saint Pius X Press our goal is to remain faithful to the original in both photographic reproductions and in textual reproductions that are reprinted. Photographic reproductions are given a page by page inspection, whereas textual reproductions are proofread to correct any errors in reproduction.