Since the preceding sermon touched only the beginnings of the apostolic reading, let us now hear concerning those things which follow what the Lord inspires; for thus he began: 'I beseech you,' he says, 'by the mercy of God, that you present your bodies a living sacrifice' (Rom. 12). Does the Apostle, in speaking thus, approve only bodies as worthy of divine sacrifices, and either pass over souls in silence as reprobate, or omit them, or leave them aside? Is not the soul from heaven, the body from earth; the one is ruled, the other rules; the one governs, the other serves; the one lives, the other gives life; the one abides, the other fails; the one suffers the ages, the other knows them not; and, at the last, does not death, which lords it only over the body, not even touch it while the soul is present?
And what is the reason that the soul is passed over in silence, and only the body is thus called to be God's sacrifice? Brethren, here the Apostle honors the body, he does not diminish the soul. For the body, which sins seize, which faults bind, which crimes weigh down, which vices corrupt, which passions cast down — this the Apostle desires to loose, strives to liberate, labors to lift up, contends to expiate, that the body may ascend to the origin of the soul, and not the soul descend to the nature of the body; and that the body may accompany the soul to heaven, and not the soul follow the body to earth. Hear the Scripture telling with what and how great torments of the body the soul is weighed down: 'The body, which is corrupted, weighs down the soul, and the earthly dwelling presses down the sense that muses upon many things' (Wisd. 9).
Therefore the Apostle wishes not that the soul be laid down, but that the body be lifted up; and that both the soul and the body, that is, the whole man, may come to a holy sacrifice, to an offering pleasing to God. But that the soul also is God's sacrifice, the Psalmist declares, saying: 'A sacrifice to God is a troubled spirit' (Ps. 50). 'That you present your bodies a living sacrifice, holy, pleasing to God.' Because man is pleasing not from the fact that he lives, but is pleasing from the fact that he lives well; nor is man a sacrifice from the fact that he offers himself to God, but if he offers himself to God in a holy manner. For as much as an unspotted victim pleases God, so much does a victim, if it be spotted, exasperate God.
Hear God saying: 'You shall not offer to me the lame, nor the one-eyed, nor one polluted by the thought of death, but the mature, without blemish' (Lev. 22). Hence it is that the Apostle asks for God a living victim. Therefore, brethren, if we ourselves are the incense of His own propitiation... (Some words are wanting.) Cain proves this, who, ungrateful priest, so divided with God the little from that whole which he had received, that what was worst he burned upon the altar, but what was best he reserved to his own offence; and at last, dividing his own things ill with his own Author, he divided off himself and his posterity both from life and from the human race (Gen. 4). Let us therefore follow Abel to the reward, not accompany Cain to the punishment. Abel, bearing a lamb to God's sacrifice, is taken up like a lamb;
Cain, carrying stubble for himself, found for himself the tinder by which he should be burned. 'That you present your bodies a living sacrifice, holy, pleasing to God, your reasonable service.' As much as a service leaning upon reason appeases God, so much does that which has no reason exasperate Him. A reasonable service — one which is not disturbed by presumption, not confounded by rashness, not violated by unlawful things, not disguised by pretense. At the service of a king the military post trembles; human dominion demands anxious servitude; at the will of the one commanding, the fear of the one obeying keeps watch; and a cautious devotion acquires the reward of just recompense, while a presumptuous servitude does not escape the penalty of rashness.
Who, unbidden, rushes into the servitude of the royal court? Who without a commission has dared to profess himself a soldier? Who without the insignia of rank has usurped the name of rank? And if these things among men are anxious and cautious, if they stand by rank, if they gain strength by order, if they are preserved by trembling awe, how much more, before God, is devotion cautious, servitude to be trembled at, and worship anxious, that it may render divine service by reason? 'Your reasonable service,' he says. A service glowing with reason is fervor; but that which is not bridled by reason is frenzy. Hence the Jewish people, while it seeks for itself a God contrary to reason, lost the God whom it served with reason (Exod. 32).
Hence the sons of Aaron, while they are unmindful of reason, while they presume to bring earthly fires near to the divine fires, changed the flame of the saving sacrifice into a penal conflagration for themselves (Lev. 10). Hence Saul, swelling with the royal crown, while he thinks that something of the priesthood also is lawful for him, lost, as a profaner of the altar, the kingdom which he had received (1 Sam. 15). Hence the Jew, while he cultivates the Law without the reason of the Law, slew the Author of the Law. Hence the Gentile, while, ignorant of reason, he obeys the peoples of gods and the monsters of gods, did not deserve to arrive at the servitude of God, who is one and true. Hence Arius thinks to serve the Father by blaspheming the Son; and while he gives a beginning to the Son, the wretch imposes an end upon the Father.
Hence Photinus, while he denies that the Son is co-eternal with the Father, labors to prove that the Father, as Father, has not always existed. Hence all heresies, while they are borne toward injury of the Godhead, while they lie about the Trinity in their words, do homage by blasphemies. But let us, brethren, both fit our bodies into a living sacrifice to God, and procure that our service be reasonable, so that there may be true faith, a pure conscience, a sober mind, a firm hope, a clean heart, a chaste flesh, a holy sense, a devout soul, a safe reason, a chaste charity, a generous mercy, a holy life, a modest bearing; and let humility always accompany our every step toward all obedience to Christ.