2Pet 2:22

“There has appeared one, Noetus by name, and by birth a native of Smyrna. This person introduced a heresy from the tenets of Heraclitus. Now a certain man called Epigonus becomes his minister and pupil, and this person during his sojourn at Rome disseminated his godless opinion. But Cleomenes, who had become his disciple, an alien both in way of life and habits from the Church, was wont to corroborate the (Noetian) doctrine. At that time, Zephyrinus imagines that he administers the affairs of the Church -an uninformed and shamefully corrupt man. And he, being persuaded by proffered gain, was accustomed to connive at those who were present for the purpose of becoming disciples of Cleomenes. But (Zephyrinus) himself, being in process of time enticed away, hurried headlong into the same opinions; and he had Callistus as his adviser, and a fellow-champion of these wicked tenets. But the life of this (Callistus), and the heresy invented by him, I shall after a little explain. The school of these heretics during the succession of such bishops, continued to acquire strength and augmentation, from the fact that Zephyrinus and Callistus helped them to prevail. Never at any time, however, have we been guilty of collusion with them; but we have frequently offered them opposition, and have refuted them, and have forced them reluctantly to acknowledge the truth. And they, abashed and constrained by the truth, have confessed their errors for a short period, but after a little, wallow once again in the same mire.”

“Shall we then seek precepts of living from these men, who have no other feelings than those of the irrational creatures? The Cyrenaics say that virtue itself is to be praised on this account, because it is productive of pleasure. True, says the filthy dog, or the swine wallowing in the mire. For it is on this account that I contend with my adversary with the utmost exertion of strength, that my valour may procure for me pleasure; of which I must necessarily be deprived if I shall come off vanquished. Shall we therefore learn wisdom from these men, who differ from cattle and the brutes, not in feeling, but in language? To regard the absence of pain as the chief good, is not indeed the part of Peripatetic and Stoic, but of clinical philosophers. For who would not imagine that the discussion was carried on by those who were ill, and under the influence of some pain? What is so ridiculous, as to esteem that the chief good which the physician is able to give? We must therefore feel pain in order that we may enjoy good; and that, too, severely and frequently, that afterwards the absence of pain may be attended with greater pleasure. He is therefore most wretched who has never felt pain, because he is without that which is good; whereas we used to regard him as most happy, because he was without evil. He was not far distant from this folly, who said that the entire absence of pain was the chief good. The forbidding of the flesh of swine also has the same intention; for when God commanded them to abstain from this, He willed that this should be especially understood, that they should abstain from sins and impurities. For this animal is filthy and unclean. Therefore He forbade them to use the flesh of the pig for food, that is, not to imitate the life of swine, which are nourished only for death; lest, by devoting themselves to their appetite and pleasures, they should be useless for working righteousness, and should be visited with death. Also that they should not immerse themselves in foul lusts, as the sow, which wallows in the mire.”

“But it is happened unto them, according to the true proverb,.... Which is true, both in fact and in the application of it, and which lies in the Scriptures of truth, at least the first part of it, Pro 26:11. The dog is turned to his own vomit again, and the sow that was washed to her wallowing in the mire; which expresses the filthy nature of sin, signified by vomit, mire, and dirt, than which nothing is more abominable and defiling; and also the just characters of these apostates, who are filly compared to dogs and swine and likewise their irreclaimable and irrecoverable state and condition, it being impossible they should be otherwise, unless their natures were changed and altered. In the Hebrew language, a "sow" is called from the root which signifies to "return", because that creature, as soon as it is out of the mire and dirt, and is washed from its filthiness, naturally returns to it again: so such apostates return to what they were before, to their former principles and practices: in this manner the Jews explain the proverb, "Tobiah returns to Tobiah, as it is said, Pro 26:11; as a dog returneth to his vomit (r).'' (r) Vajikra Rabba, sect. 16. fol. 158. 4. Next: 2 Peter Chapter 3”

“According to the true proverb - This seems to be a reference to Pro 26:11 : ככלב שב אל קאו kekeleb shab al keo; as the dog returneth to his vomit, so a fool repeateth his folly. In substance this proverb is found among the rabbins; so Midrash Ruth, in Sohar Chadash, fol. 62: Orphah is returned to her mire, Ruth persevered in spirit; and again, Ibid. fol. 64: "Orphah, which is נפש הבהמית nephesh habbehemith, the bestial soul, is returned to her mire." The Greeks have something like it; so Arrian, Dissert. Epict. l. iv. c. 11, says: Απελθε και χοιρῳ διαλεγου, ἱν' εν βορβορῳ μη κυλιηται, "Go and reason with the swine, lest he be rolled in the mire." This is called a true proverb: for it is a fact that a dog will eat up his own vomit; and the swine, howsoever carefully washed, will again wallow in the mire. As applied here it is very expressive: the poor sinner, having heard the Gospel of Christ, was led to loathe and reject his sin; and, on his application to God for mercy, was washed from his unrighteousness. But he is here represented as taking up again what he had before rejected, and defiling himself in that from which he had been cleansed. Here is a sad proof of the possibility of falling from grace, and from very high degrees of it too. These had escaped from the contagion that was in the world; they had had true repentance, and cast up "their soursweet morsel of sin;" they had been washed from all their filthiness, and this must have been through the blood of the Lamb; yet, after all, they went back, got entangled with their old sins, swallowed down their formerly rejected lusts, and rewallowed in the mire of corruption. It is no wonder that God should say, the latter end is worse with them than the beginning: reason and nature say it must be so; and Divine justice says it ought to be so; and the person himself must confess that it is right that it should be so. But how dreadful is this state! How dangerous when the person has abandoned himself to his old sins! Yet it is not said that it is impossible for him to return to his Maker; though his case be deplorable, it is not utterly hopeless; the leper may yet be made clean, and the dead may be raised. Reader, is thy backsliding a grief and burden to thee? Then thou art not far from the kingdom of God; believe on the Lord Jesus, and thou shalt be saved.”

“But--You need not wonder at the event; for dogs and swine they were before, and dogs and swine they will continue. They "scarcely" (Pe2 2:18) have escaped from their filthy folly, when they again are entangled in it. Then they seduce others who have in like manner "for a little time escaped from them that live in error" (Pe2 2:18). Peter often quoted Proverbs in his First Epistle (Pe1 1:7; Pe1 2:17; Pe1 4:8, Pe1 4:18); another proof that both Epistles come from the same writer. Next: 2 Peter Chapter 3”