1 Corinthians 5:6 Douay-Rheims

Your glorying is not good. Know you not that a little leaven corrupteth the whole lump?

Thomas Aquinas

1225–1274 Catholic

Above, the Apostle recalled a twofold fault: namely, that of the fornicating Corinthian, and of the others who were tolerating his sin; here he rebukes both faults. First, the fault of those tolerating his sin; second, the fault of the fornicator, there: "the body however is not for fornication," etc. Concerning the first he does two things. First, he rebukes in the Corinthians the negligence of judgment; second, he rebukes in them certain other vices concerning judgment, chapter VI: "does anyone dare," etc. Concerning the first he does two things. First, he rebukes those who did not separate the fornicator from themselves; second, he refutes the false understanding which they had conceived from his words, there: "I wrote to you in the epistle," etc. Concerning the first he does two things. First, he reproves what they had done; second, he shows what is to be done, there: "purge out the old leaven," etc. Concerning the first he does two things. First, he reproves the past fault as to its root.

For he had said above that from their being puffed up there follows in them a lack of compassion, and from the lack of compassion, negligence of correction. First, therefore, he argues against the elation of the Corinthians, saying, "your boasting is not good," namely, by which you boast in the defects of others, as though you yourselves were innocent. For each one ought to glory in the Lord concerning the goods divinely given to himself, not concerning others, according to that word of Gal. VI, 4: "but let each one prove his own work, and so he will have glory in himself, and not in another." But it is especially evil to glory in the evils of others. For it is said in Ps. LI, 3: "why do you glory in malice?"

Second, he assigns the reason for what he had said, saying, "do you not know that a little leaven corrupts the whole lump?" As if to say: you cannot be ignorant of this. Now it must be known that two things can be considered in leaven. First, the flavor which it gives to the bread, and according to this, by leaven is signified the wisdom of God, through which all the things that belong to man are made flavorful; and according to this it is said in Matth. XIII, 33: "the kingdom of heaven is like leaven, which a woman took and hid in three measures of flour, until the whole was leavened." Second, corruption can be considered in leaven, and according to this, by leaven can be understood, in one way, sin, because indeed through one sin of a man all his works are rendered corrupt, as for instance through the sin of pretense, which is compared to leaven. Lc. XII, 1: "beware of the leaven of the Pharisees, which is hypocrisy." In another way, by leaven can be understood the sinful man, and it is to this that this comparison is brought in. For just as through a little leaven the whole mass of dough is corrupted, so through one sinner the whole society is defiled. Hence Eccli. XI, 34: "from one spark the fire is increased, and from one deceitful man blood is increased." And this indeed happens, when through the sin of one, others are in some way provoked to sin. Or also when they consent to the one sinning, at least by not correcting him when they are able to correct, according to that word of Rom. I, 32: "they are worthy of death, not only they who do these things, but also they who consent to those doing them." And therefore the Corinthians ought not to glory in the sin of one, but rather to take care lest, through the sin of one, all be defiled by association with him, according to that word of Cant. II, 2: "as the lily among thorns, so is my beloved among the daughters," where the Gloss says: "he was not good, who could not tolerate the wicked."

Then, when he says, "purge out the old leaven," he shows what is to be done for the rest. And first he sets down the teaching; second he assigns the reason, there: "our Passover," etc. He says therefore first: because "a little leaven corrupts the whole lump," therefore "purge out the old leaven," that is, purge yourselves, by casting away from you the old leaven, that is, the fornicator, who by sinning has returned to the oldness of ancient corruption, according to that word of Baruch III, 11: "you have grown old in a foreign land, you have been defiled with the dead." Which indeed he says, because through the separation of one sinner the whole society is purged. Hence also, when Judas had gone out, the Lord said, Io. XIII, 31: "now is the Son of man glorified." By the old leaven can also be understood ancient error, according to that word of Is. XXVI, 3: "the old error has departed," or also the corruption of original sin, according to that word of Rom. VI, 6: "our old man has been crucified together with him," or also any actual sin whatsoever, according to that word of Col. III, 9: "stripping yourselves of the old man with his deeds": for by the admonition of these a man is purged.

He then sets down consequently the effect of the purging, saying, "that you may be a new mixture." Now "mixture" is said to be the commingling of water and new flour, before leaven is mixed in. Therefore, with the leaven removed from the faithful, that is, the sinner, or the sin, they remain as a new mixture, that is, in the purity of their newness, according to that word of Ps. CII, 5: "your youth will be renewed like the eagle's"; Eph. IV, v. 23: "be renewed in the spirit of your mind." Then he sets down the due manner of the purging when he says, "as you are unleavened," that is, without the leaven of sin. For it is said from "a," which is "without," and "zyma," which is "leaven." Hence the Lord, Matth. XVI, 6, says to the disciples, "beware of the leaven of the Pharisees and Sadducees."

Then, when he says, "for indeed our Passover," he assigns the reason for what he had said, namely why the faithful ought to be unleavened, which reason indeed is taken from the mystery of Christ's passion. Hence first he sets forth the mystery itself; second he concludes his proposition, there: "therefore let us feast," etc. Concerning the first it must be considered that among the other sacraments of the law the most celebrated was the paschal lamb, which, as is commanded in Ex. XII, 1 ff., was immolated by the whole multitude of the sons of Israel in memory of that benefit, by which the Angel striking the firstborn of Egypt passed over the houses of the Jews, whose doors had been smeared with the blood of the lamb. Hence the name of Pasch is taken, according to what is said there: "for it is the phase," that is, "the passing over of the Lord"; and finally by the power of this benefit the people crossed the Red Sea, as is said in Ex. XIV, 15 ff. For that lamb was a figure of the innocent Christ, of whom it is said, Io. I, 29: "behold the Lamb of God." Therefore, just as that figural lamb was immolated by the sons of Israel, that the people of God might be freed from the striking Angel, and that they might cross the Red Sea, freed from the servitude of Egypt, so Christ was slain by the sons of Israel, through whose blood the people of God is freed from the assault of the Devil and from the servitude of sin, through Baptism as through the Red Sea. That figural lamb, however, was called the Pasch of the Jews, because it was immolated as a sign of the passing over. Hence it is said, Matth. XXVI, 17: "where do you wish that we prepare for you to eat the Pasch?" That is, the paschal lamb.

The Apostle says therefore: for this reason you ought to be unleavened, "for indeed," that is, because, just as the figural Pasch of the old people is the lamb immolated, so "our Passover," that is, of the new people, "is Christ, immolated," to whose immolation also the name of Pasch is fitting, both by the signification of the Hebrew tongue, which signifies passing-over, Ex. XII, 11: "for it is the phase," that is, "the passing over," and by the signification of the Greek tongue, insofar as the name Pasch signifies passion. For Christ, through the passion by which he was immolated, passed over from this world to the Father, as is said in Io. XIII, 1.

Then, when he says, "therefore let us feast," he concludes his proposition. For the evidence of this it must be considered that, as is read in Ex. XII, 8, the paschal lamb after its immolation was eaten with unleavened breads. Therefore, just as the figural lamb was a figure of our immolated Passover, so the figural paschal observance ought to be conformed to the observance of the new Passover. Therefore, because Christ immolated is our Passover, "therefore let us feast," namely, eating Christ, not only sacramentally, according to that word of Io. VI, v. 54: "unless you eat the flesh of the Son of man, and drink his blood, you will not have life in you," but also spiritually, by enjoying his wisdom, according to that word of Eccli. XXIV, v. 29: "they who eat me shall still hunger, and they who drink me shall still thirst," and thus with spiritual joy, according to that word of Ps. XLI, 5: "with the voice of exultation and confession, the sound of one feasting."

Then he determines the manner of feasting according to the conformity of the truth to the figure, saying, "not in the old leaven, nor in the leaven of malice and wickedness." For it was commanded in Ex. XII, 15, that no leaven at all should be found in the houses of those eating the paschal lamb. Leaven, however, has both oldness and corruption. Hence by the removal of leaven, first indeed can be understood the removal of the observance of the precepts of the old law, which through the passion of Christ has been put to death, according to that word of Lev. c. XXVI, 10: "you will cast away the old things, when the new come upon you." Second, by the removal of leaven can be understood the removal of the corruption of sin, as was said above, that "a little leaven corrupts the whole lump." And as to this he adds, "nor in the leaven of malice and wickedness," so that malice is referred to the perversity of the deed, according to that word of Iac. I, v. 21: "casting away all filthiness and abundance of malice." By wickedness, however, is understood fraudulent scheming. Prov. XXVI, v. 25: "when he shall have taken up his voice, do not believe him, for there are seven wickednesses in his heart." Or, according to the Gloss, when he says, "not in the old leaven," he removes the oldness of sin in common. But what he adds, "nor in the leaven of malice and wickedness," explains sin part by part, so that malice is said to be the sin which is committed against oneself, wickedness the sin which is committed against another.

Having therefore excluded the undue manner of feasting, he determines the fitting manner, adding, "but in the unleavened bread of sincerity and truth," that is, in sincerity and truth, which are signified by the unleavened bread. Now sincerity is set against the corruption of sin, which he signified when he said, "not in the leaven of malice and wickedness." For that is called sincere which is without corruption. Hence in II Cor. II, 17 it is said: "we are not like many, adulterating the word of God, but from sincerity we speak in Christ." Truth, however, is set against the figures of the old law, as in Io. I, v. 17 it is said, "truth and grace was made through Jesus Christ," because indeed we ought to celebrate the true Passover with truth and not with figures. Hence, according to the Gloss, by sincerity is understood innocence from vices, or newness of life; by truth, however, the justice of good works, or rectitude, which excludes fraud.

Source details
1272 · Commentary on 1 Corinthians, ch. 5, l2

English is machine-translated from the public-domain Latin (Corpus Thomisticum, Thomas Aquinas's own autograph text), since no public-domain English translation exists. It is not a scholarly translation. Please report errors.

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