8 But when He had said, “your reward is great,” he added also another consolation, saying, “For so persecuted they the prophets which were before you.”
Thus, since that first, the promise of the Kingdom, was yet to come, and all in expectation, He affords them comfort from this world; from their fellowship with those who before them had been ill-treated.
For “think not,” says He, “that for something inconsistent in your sayings and enactments ye suffer these things: or, as being teachers of evil doctrines, you are to be persecuted by them; the plots and dangers proceed not of any wickedness in your sayings, but of the malice of those who hear you. Wherefore neither are they any blame to you who suffer wrong, but to them who do the wrong. And to the truth of these things all preceding time bears witness. For against the prophets they did not even bring any charge of transgressing the law, and of sentiments of impiety, that they stoned some, chased away others, encompassed others with innumerable afflictions. Wherefore let not this trouble you, for of the very same mind they do all that is done now.” Do you see how He raised up their spirits, by placing them near to the company of Moses and Elias?
Thus also Paul writing to the Thessalonians, says, “For you became followers of the Churches of God, which are in Judea; for you also have suffered the same things of your own fellow-countrymen, even as they have of the Jews: who both killed the Lord Jesus, and their own prophets, and have driven us out; and they please not God, and are contrary to all men.” Which same point here also Christ has established.
And whereas in the other beatitudes, He said, “Blessed are the poor,” and “the merciful;” here He has not put it generally, but addresses His speech unto themselves, saying, “Blessed are you, when they shall revile you, and persecute you, and say every evil word:” signifying that this is a special privilege of theirs; and that beyond all others, teachers have this for their own.
At the same time He here also covertly signifies His own dignity, and His equality in honor with Him who begot Him. For “as they on the Father's account,” says He, “so shall you also for me suffer these things.” But when He says, “the prophets which were before you,” He implies that they were also by this time become prophets.
Next, declaring that this above all profits them, and makes them glorious, He did not say, “they will calumniate and persecute you, but I will prevent it.” For not in their escaping evil report, but in their noble endurance thereof, and in refuting them by their actions, He will have their safety stand: this being a much greater thing than the other; even as to be struck and not hurt, is much greater than escaping the blow.
Source: Homilies on the Gospel of St. Matthew (New Advent)