Aquinas and the Sacraments: The following article is a condensation of the writings of St. Thomas Aquinas in Summa contra Gentiles and Summa Theologica. As can be seen, Aquinas relied heavily on Scriptural passages, as well as the writings of various Church Fathers. St. Augustine says (De Civ. Dei x): The visible sacrifice is the sacrament. This is the sacred sign of the invisible sacrifice. A thing is called a sacrament, either by having a certain hidden sanctity, and in this sense a sacrament is a sacred secret; or from having some relationship to this sanctity. A sacrament is a sign. Moreover, it is a sacred sign. Divine Wisdom provides for each thing according to its mode. Wisdom 7,1 : "she... ordered all things sweetly"; and from Matthew 25,15: "[she] gave to everyone according to his