Matthew 23:33

And this is manifest too by what comes after; He adds at least, "Ye serpents, ye generation of vipers." For as those beasts are like their parents, in the destructiveness of their venom, so also are ye like your fathers in murderousness. Ye serpents, ye generation of vipers, that is, wicked sons of wicked men, and more wicked than those who begat them. For He showeth that they are committing greater crimes, both by their committing them after those others, and by their doing much more grievous things than they, and this, while positively affirming that they never would have fallen into the same. For they add that which is both the end and the crown of their evil deeds. For the others slew them that came to the vineyard, but these, both the son, and them that were bidding them to the wedding. But these things He saith, to separate them off from the affinity to Abraham, and to show that they had no advantage from thence, unless they followed his works; wherefore also He adds, "How can ye flee from the damnation of hell," when following them that have committed such acts? And here He recalls to their remembrance John's accusation, for he too called them by this name, and reminded them of the judgment to come.

The same had been said by John the Baptist. Wherefore as of vipers are born vipers, so of your fathers who were murderers are you born murderers.

He calls them offspring of vipers, because the nature of vipers is such that the young burst the womb of their dam, and so come forth; and in like manner the Jews condemned their fathers, finding fault with their deeds. He says, How shall ye escape the damnation of hell? By building the tombs of the saints? But the first step of piety is to love holiness, the next, to love the saints; for it is not reasonable in him to honour the righteous, who despises righteousness. The saints cannot be friends to those to whom God is an enemy. Shall ye be saved by a mere name, because ye seem to be among God's people! Forasmuch as an open enemy is better than a false friend, so is he more hateful to God, who calls himself the servant of God, and does the commands of the Devil. Indeed, before God he who has resolved to kill a worm is a murderer before the deed is done, for it is the will that is rewarded for good, or punished for evil. Deeds are evidence of the will. God then does not require deeds on His own account that He may know how to judge, but for the sake of other men, that they may perceive that God is righteous. And God affords the opportunity of sin to the wicked, not to make them sin, but to manifest the sinner; and also to the good He gives opportunity to show the purpose of their will. In this way then He gave the Scribes and Pharisees opportunity of showing their purposes, Behold, I send unto you Prophets, and wise men, and Scribes.

Because then they will fill up the measure of their fathers' purposes, therefore are they serpents, and an offspring of vipers.

Then, because He was searching their temper of mind, which is to the more part obscure, He doth, from those things also which they were about to perpetrate, which would be manifest to all, establish His words. For, because He had said, "Wherefore ye be witnesses unto yourselves that ye are the children of them which killed the prophets," making it evident, that of their affinity in wickedness He is speaking, and that it was a pretense to say, "We should not have been partakers with them," He added, "Fill ye up therefore the measure of your fathers," not commanding, but declaring beforehand, what was to be, that is, His own murder. Therefore, having brought in their refutation, and having shown that they were pretenses which they said in their own defense, as, for instance, "We would not have been partakers with them," (for they who refrain not from the Lord, how should they have refrained from the servants), He makes after this His language more condemnatory, calling them "serpents, and generation of vipers," and saying, "How shall ye escape the damnation of hell," at once perpetrating such things, and denying them, and dissembling your purpose? Then rebuking them more exceedingly from another cause also, He Saith, "I will send unto you prophets, and wise men, and scribes, and some of them shall ye kill and crucify, and some of them shall ye scourge in your synagogues." For that they should not say, "Though we crucified the Lord, yet from the servants we should have refrained, if we had been then;" "Behold," He saith, "I send servants also to you, prophets likewise themselves, and neither will ye spare them." But these things He saith, showing that it was nothing strange, that He should be murdered by those sons, being both murderous and deceitful, and having much guile, and surpassing their fathers in their outrages. And besides what hath been said, He shows them to be also exceedingly vainglorious. For when they say, "If we had been in the days of our fathers, we should not have been partakers with them," they spake out of vainglory, and were practising virtue in words only, but in their works doing the contrary. Ye serpents, ye generation of vipers, that is, wicked sons of wicked men, and more wicked than those who begat them. For He showeth that they are committing greater crimes, both by their committing them after those others, and by their doing much more grievous things than they, and this, while positively affirming that they never would have fallen into the same. For they add that which is both the end and the crown of their evil deeds. For the others slew them that came to the vineyard, but these, both the son, and them that were bidding them to the wedding. But these things He saith, to separate them off from the affinity to Abraham, and to show that they had no advantage from thence, unless they followed his works; wherefore also He adds, "How can ye flee from the damnation of hell," when following them that have committed such acts? And here He recalls to their remembrance John's accusation, for he too called them by this name, and reminded them of the judgment to come. Then, because they are nothing alarmed by judgment and hell, by reason of their not believing them, and because the thing is future, He awes them by the things present, and saith, "Wherefore, behold, I send unto you prophets and scribes: and some of them shall ye kill and crucify, and scourge; that upon you may come all the righteous blood shed upon the earth, from the blood of righteous Abel, unto the blood of Zacharias the son of Barschias, whom ye slew between the temple and the altar. Verily I say unto you, that all these things shall come upon this generation." See by how many things He has warned them. He said, Ye condemn your fathers, in that ye say, "We would not have been partakers with them;" and this is no little thing to shame them. He said, While ye condemn them, ye do worse things, even ye yourselves; and this is sufficient to cover