Matthew 24:1-2.
“And Jesus went out from the temple, and departed. And His disciples came to Him to show Him the buildings of the temple. And He answered and said unto them, See ye not all these things? Verily I say unto you, there shall not be left here one stone upon another, that shall not be thrown down.”
For inasmuch as He said, “Your house is left desolate,” and had previously forewarned them of many grievous things; therefore the disciples having heard these things, as though marvelling at it, came unto Him, showing the beauty of the temple, and wondering, if so much beauty was to be destroyed, and materials so costly, and variety of workmanship past utterance; He no longer thenceforth talks to them of desolation merely, but foretells an entire destruction. “See ye not all these things,” says He, and do ye marvel, and are you amazed? “There shall not remain one stone upon another.” How then did it remain? One may say. But what is this? For neither so has the prediction fallen to the ground. For He said these things either indicating its entire desolation, or at that spot where He was. For there are parts of it destroyed unto the foundations.
And together with its we would say another thing also, that from what has been done, even the most contentious ought to believe concerning the remains, that they are utterly to be destroyed.
“And as He sat upon the mount of Olives, the disciples came unto Him privately, saying, Tell us when shall these things be? And what shall be the sign of Your coming, and of the end of the world?”
Therefore did they come unto Him privately, as it was of such matters they meant to inquire. For they were in travail to know the day of His coming, because of their eager desire to behold that glory, which is the cause of countless blessings. And these two things do they ask him, when shall these things be? That is, the overthrow of the temple; and, what is the sign of your coming? But Luke says, the question was one concerning Jerusalem, as though they were supposing that then is His coming. And Mark says, that neither did all of them ask concerning the end of Jerusalem, but Peter and John, as having greater freedom of speech.
What then says He? “Take heed that no man deceive you. For many shall come in my name, saying, I am Christ, and shall deceive many. And you shall hear of wars and rumors of wars. See that you be not troubled; for all these things must come to pass, but the end is not yet.”
For since they felt as being told of vengeance falling on others when hearing of that which was to be brought upon Jerusalem and as though they were to be out of the turmoils, and were dreaming of good things only, and looked for these to befall them quite immediately; for this cause He again foretells to them grievous things, making them earnest, and commanding them on two grounds to watch, so as neither to be seduced by the deceit of them that would beguile them, nor to be overpowered by the violence of ills that should overtake them.
For the war, says He, shall be twofold that of the deceivers, and that of the enemies, but the former far more grievous, as coming upon them in the confusion and turmoils, and when men were terrified and troubled. For indeed great was the storm then, when the Roman power was beginning to flourish, and cities were taken, and camps and weapons were set in motion, and many were readily believed.
But of wars in Jerusalem is He speaking; for it is not surely of those without, and everywhere in the world; for what did they care for these? And besides, He would thus say nothing new, if He were speaking of the calamities of the world at large, which are happening always. For before this, were wars, and tumults, and fightings; but He speaks of the Jewish wars coming upon them at no great distance, for henceforth the Roman arms were a matter of anxiety. Since then these things also were sufficient to confound them, He foretells them all.
Then to show that He Himself also will assail the Jews with them, and war on them, He speaks not of battles only, but also of plagues sent from God, famines, and pestilences, and earthquakes, showing that the wars also He Himself permitted to come upon them, and that these things do not happen for no purpose according to what has been before the accustomed course of things among men, but proceed from the wrath on high.
Therefore He says, they shall come not by themselves or at once, but with signs. For that the Jews may not say, that they who then believed were the authors of these evils, therefore has He told them also of the cause of their coming upon them. “For verily I say unto you,” He said before, “all these things shall come upon this generation,” having made mention of the stain of blood on them.
Then lest on hearing of the showers of evils, they should suppose the gospel to be broken through, He added, “See, be not troubled, for all things must come to pass,” i.e. which I foretold, and the approach of the temptations will set aside none of the things which I have said; but there shall indeed be tumults and confusion, but nothing shall shake my predictions.
Then since He had said to the Jews, “You shall not see me, till you shall say, Blessed is He that comes in the name of the Lord;” and the disciples supposed that together with the destruction would be the end also; to set right this secret thought of theirs, He said, “But the end is not yet.” For that they did suspect even as I said, you may learn from their question. For, what did they ask? When shall these things be? i.e. when shall Jerusalem be destroyed? And what is the sign of Your coming, and of the end of the world?
But He answered nothing directly to this question, but first speaks of those other things that are urgent, and which it was needful for them to learn first. For neither concerning Jerusalem straightway, nor of His own second coming, did He speak, but touching the ills that were to meet them at the doors. Wherefore also He makes them earnest in their exertions, by saying, “Take heed that no man deceive you; for many shall come in my name, saying, I am Christ.”
Afterwards, when He has roused them to listen about these things (for, “take heed,” says He, “that no man deceive you”); and having made them energetic, and prepared them to be watchful, and has spoken first of the false Christs, then He speaks of the ills of Jerusalem, assuring them ever by the things already past, foolish and contentious though they were, of those which were yet to come.
2. But by “wars and rumors of wars,” He means, what I before said, the troubles coming upon them. After this, because, as I have already said, they supposed after that war the end would come, see how He warns them, saying, “But the end is not yet. For nation,” He says, “shall rise against nation, and kingdom against kingdom.” Of the preludes to the ills of the Jews does He speak. “All these are the beginning of sorrows,” that is, of those that befall them. “Then shall they deliver you up to be afflicted, and shall kill you.”
In good season did He introduce their ills, having a consolation from the common miseries; and not in this way only, but also by His adding, that it is “for my name's sake. For you shall be hated,” He says, “of all men for my name's sake. Then shall many be offended, and shall betray one another, and many false Christs and false prophets shall arise, and shall deceive many. And because iniquity shall abound, the love of many shall wax cold; but he that shall endure unto the end, the same shall be saved.”
This is the greater evil, when the war is intestine too, for there were many false brethren. Do you see the war to be threefold? From the deceivers, from the enemies, from the false brethren. See Paul too lamenting over the same things, and saying, “Without were fightings, within were fears;” and, “perils among false brethren,” and again, “For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.”
Source: Homilies on the Gospel of St. Matthew (New Advent)