“Woe unto you, because ye build the tombs of the prophets, and garnish their sepulchers, and say, If we had been in the days of our fathers, we would not have been partakers with them in the blood of the prophets.”
Not because they build, nor because they blame the others, does He say, woe, but because, while both thus, and by what they say, they are pretending to condemn their fathers, they do worse. For in proof that the condemnation was a pretense, Luke says, you do allow because ye build; for, “Woe unto you,” says He, “for you build the sepulchers of the prophets, and your fathers killed them. Truly ye bear witness, and you allow the deeds of your fathers, for they indeed killed them, and you build their sepulchers.” For here He reproves their purpose, wherewith they built, that it was not for the honoring of them that were slain, but as making a show of the murders, and afraid, lest, when the tombs had perished by time, the proof and memory of such daring should fade away, setting up these glorious buildings, as a kind of trophy, and priding themselves in the daring deeds of those men, and displaying them.
For the things that you now dare to do, show that you do these things also in this spirit. For, though ye speak the contrary, says He, as condemning them, as, for instance, “We should not, if we had been in their days, have been partakers with them;” yet the disposition is evident wherewith ye say these things. Wherefore also unfolding it, though darkly, still He has expressed it. For when He had said, you say, “If we had been in the days of our fathers, we should not have been partakers with them in the blood of the prophets;” He added, “Wherefore ye be witnesses unto yourselves, that you are the children of them that slew the prophets.” And what blame is it to be a murderer's son, if one partake not in the mind of one's father? None. Whence it is evident, that for this same thing He brings it forward against them, hinting at their affinity in wickedness.
And this is manifest too by what comes after; He adds at least, “You serpents, you generation of vipers.” For as those beasts are like their parents, in the destructiveness of their venom, so also are you like your fathers in murderousness.
Then, because He was searching their temper of mind, which is to the more part obscure, He does, 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 you 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 you 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 says, “I will send unto you prophets, and wise men, and scribes, and some of them shall you kill and crucify, and some of them shall you 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 says, “I send servants also to you, prophets likewise themselves, and neither will you spare them.” But these things He says, 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 has 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 spoke out of vainglory, and were practising virtue in words only, but in their works doing the contrary.
You serpents, you generation of vipers, that is, wicked sons of wicked men, and more wicked than those who begot them. For He shows 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 says, 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 you 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 says, “Wherefore, behold, I send unto you prophets and scribes: and some of them shall you 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 Barachias, whom you slew between the temple and the altar. Verily I say unto you, that all these things shall come upon this generation.”
2. See by how many things He has warned them. He said, You condemn your fathers, in that you say, “We would not have been partakers with them;” and this is no little thing to shame them. He said, While ye condemn them, you do worse things, even ye yourselves; and this is sufficient to cover them with disgrace. He said, These things shall not be without punishment; and hence he implants in them fear beyond words. He has reminded them at least of hell. Then because that was to come, He brought home to them the terrors as even present. “For all these things shall come,” He says, “upon this generation.”
He added also unspeakable severity to the vengeance, saying, that they shall suffer more grievous things than all; yet by none of these things did they become better. But if any one say, And why do they suffer more grievously than all? We would say, Because they have first committed more grievous things than all, and by none of the things that have been done to them have they been brought to a sound mind.
Heardest thou not Lamech saying, “Of Lamech vengeance shall be taken seventy times sevenfold;” that is, “I am deserving of more punishment than Cain.” Why could this be? Yet he did not slay his brother; but because not even by his example was he brought to a better mind. And this is what God says elsewhere, “Requiting the sins of fathers upon children for the third and fourth generation of them that hate me.” Not as though one were to suffer punishment for the crimes committed by others, but inasmuch as they who, after many sin and have been punished, yet have not grown better, but have committed the same offenses, are justly worthy to suffer their punishments also.
But see how seasonably he also mentioned Abel, indicating that this murder likewise is of envy. What then have ye to say? Do you not know what Cain suffered? Did God hold His peace at his deeds? Did He not exact the severest penalty? Heard ye not what things your fathers suffered, when they slew the prophets; were they not delivered over to punishments, and inflictions of vengeance without number? How then did ye not become better? And why do I speak of the punishments of your fathers, and what they suffered? Thou who yourself condemnest your fathers, how is it you do worse? For moreover even ye yourselves have declared that “He will miserably destroy those wicked men.” What favor then will you have after this, committing such things after such a sentence?
Source: Homilies on the Gospel of St. Matthew (New Advent)