"Summa Theologica" is considered Aquinas' greatest work and most complete explanation of his theology. Part 3 focuses on Christ being the way to God and the necessity of the incarnation.

The Book of Causes, highly influential in the medieval university, was commonly but incorrectly understood to be the completion of Aristotle's metaphysics. It was Thomas Aquinas who first judged it to have been abstracted from Proclus's Elements of Theology, presumably by an unknown Arabic author, who added to it ideas of his own. The Book of Causes is of particular interest because themes that appear in it are echoed in the metaphysics of Aquinas: its treatment of being (esse) as proceeding from the First Creating Cause; the triadic scheme of being, living, and knowing; and the general scheme of participation in which "all is in all." Thus, the Book of Causes provides a historical backdrop for understanding and appreciating Aquinas's development of these themes in his metaphysics. Thomas's Commentary on the Book of Causes, composed during the first half of 1272, is a distinct philosophical work in its own right. It provides an extended view of his approach to Neoplatonic thought and functions as a guide to his metaphysics. Though long neglected and, until now, never translated into English, it deserves an equal place alongside his commentaries on Aristotle and Boethius. In addition to the extensive annotation, bibliography, and thorough introduction, this translation is accompanied by two valuable appendices. The first provides a translation of another version of proposition 29 of the Book of Causes, which was not known to St. Thomas. The second lists citations of the Book of Causes found in the works of St. Thomas and cross-references these to a list showing the works, and the exact location within them, where the citations can be found.

Among the great works of Thomas Aquinas, the ""Commentary on the Sentences of Peter Lombard"" has suffered almost total neglect among translators. Such neglect is surprising, considering that the massive Commentary - more than 4,000 pages in the last printed edition - is not only Aquinas' first systematic engagement with all the philosophical and theological topics on which he expended his energy over the span of a short career but is also characterized by an exuberance and elaborateness seldom found in his subsequent writings. Although Chenu had already drawn attention decades ago to the importance of studying this youthful tour de force for a fuller understanding of Thomas' more mature work, the ""Commentary on the Sentences"" has remained a closed book for many modern students of Thomistic and medieval thought because of its relative inaccessibility in English or in Latin.The present volume, containing all the major texts on love and charity, makes available what is by far the most extensive translation ever to be made from the Commentary with the added benefit that the better part of the translation is based on the (as yet unpublished) critical edition of the Leonine Commission. The collection of texts from all four books has a tight thematic coherence that makes it invaluable to students of Thomas' moral philosophy, moral theology, and philosophical theology. In addition, the inclusion of parallel texts from Aquinas' first (Parisian) Commentary as well as from his second (Roman) attempt at a commentary, the recently rediscovered ""Lectura Romana"", makes this edition all the more valuable for those who wish to track the internal development of Thomas' thinking on these matters.The new availability of so many rich passages from the ""Commentary on the Sentences"" will encourage and facilitate use of a magnificent resource that deserves to be better known.

"An Introduction to the Metaphysics of St. Thomas Aquinas" is an accessible Aquinas and a solid entry into his work. The format is manageable, and the scope, appropriately limited. James F. Anderson's skillful collection and lucid translation makes the pleasure of reading Aquinas available as it has not been before.

Saint Thomas Aquinas compiled a set of catechetical instructions. This books follows the basic plan of a catechism, beginning with the Apostle's Creed. This if followed by ten Commandments and an explanation of the Sacraments. This work closes with a section on the Lord's Prayer, commonly known as the Our Father and on the Hail Mary.