Thomas Aquinas

“ Art. 3 - Whether the offering of sacrifice is a special act of virtue? Objection 1: It would seem that the offering of sacrifice is not a special act of virtue. Augustine says (De Civ. Dei x, 6) : "A true sacrifice is any work done that we may cleave to God in holy fellowship." But not every good work is a special act of some definite virtue. Therefore the offering of sacrifice is not a special act of a definite virtue. ”

“ There is a sacrifice which is deserving of praise merely through being offered to God in protestation of our subjection to God: and the obligation of offering this sacrifice was not the same for those under the New or the Old Law, as for those who were not under the Law. For those who are under the Law are bound to offer certain definite sacrifices according to the precepts of the Law, whereas those who were not under the Law were bound to perform certain outward actions in God's honor, as became those among whom they dwelt, but not definitely to this or that action. ”

“ But it happens that the acts of the other virtues are directed to the reverence of God, as when a man gives alms of his own things for God's sake, or when a man subjects his own body to some affliction out of reverence for God; and in this way the acts also of other virtues may be called sacrifices. On the other hand there are acts that are not deserving of praise save through being done out of reverence for God: such acts are properly called sacrifices, and belong to the virtue of religion. ”