1 Corinthians 5:7

"Purge out the old leaven," that is, this evil one. Not that he speaketh concerning this one only; rather he glances at others with him. For, "the old leaven" is not fornication only, but also sin of every kind. And he said not, "purge," but "purge out;" "cleanse with accuracy so that there be not so much as a remnant nor a shadow of that sort." In saying then, "purge out," he signifies that there was still iniquity among them. But in saying, "that ye may be a new lump, even as ye are unleavened," he affirms and declares that not over very many was the wickedness prevailing. But though he saith, "as ye are unleavened," he means it not as a fact that all were clean, but as to what sort of people you ought to be. "For our Passover also hath been sacrificed for us, even Christ; wherefore let us keep the feast: not with old leaven, nor with the leaven of malice and wickedness, but with the unleavened bread of sincerity and truth." So also Christ called His doctrine Leaven. And further he himself dwells upon the metaphor, reminding them of an ancient history, and of the Passover and unleavened bread, and of their blessings both then and now, and their punishments and their plagues. It is festival, therefore, the whole time in which we live. For though he said, "Let us keep the feast," not with a view to the presence of the Passover or of Pentecost did he say it; but as pointing out that the whole of time is a festival unto Christians, because of the excellency of the good things which have been given. For what hath not come to pass that is good? The Son of God was made man for thee; He freed thee from death; and called thee to a kingdom. Thou therefore who hast obtained and art still obtaining such things, how can it be less than thy duty to "keep the feast" all thy life? Let no one then be downcast about poverty, and disease, and craft of enemies. For it is a festival, even the whole of our time. So that by means of this example also he mightily drives the fornicator out of the Church. For, saith he, so far from his presence profiting, he even doth harm, injuring the common estate of the body. For one knows not whence is the evil savor while the corrupt part is concealed, and so one imputes it to the whole. Wherefore he urges upon them strongly to "purge out the leaven, that ye may be," saith he, "a new lump, even as ye are unleavened." "For our Passover hath been sacrificed for us even Christ." He said not, hath died, but more in point to the subject in hand, "hath been sacrificed." Seek not then unleavened bread of this kind, since neither hast thou a lamb of the same kind. Seek not leaven of this description, seeing that thine unleavened bread is not such as this. Thus, in the case of material leaven, the unleavened might become leavened, but never the reverse; whereas here there is a chance of the direct contrary occurring. This however he has not plainly declared: and observe his good sense. In the former Epistle he gives the fornicator no hope of return, but orders that his whole life should be spent in repentance, lest he should make him less energetic through the promise. For he said not, "Deliver him up to Satan," that having repented he might be commended again unto the Church. But what saith he? "That he may be saved in the last day." For he conducts him on unto that time in order to make him full of anxiety. And what favors he intended him after the repentance, he reveals not, imitating his own Master. For as God saith, "Yet three days, and Nineveh shall be overthrown," and added not, "but if she repent she shall be saved:" so also he did not say here, "But if he repent worthily, we will 'confirm our love towards him.'" But he waits for him to do the work that so he may then receive the favor. For if he had said this at the beginning he might have set him free from the fear. Wherefore he not only does not so, but by the instance of leaven allows him not even a hope of return, but reserves him unto that day: "Purge out