Matt. XVII. 10.
“And His disciples asked Him, saying, Why then say the Scribes that Elias must first come?”
Not then from the Scriptures did they know this, but the Scribes used to explain themselves, and this saying was reported abroad among the ignorant people; as about Christ also.
Wherefore the Samaritan woman also said, “Messiah comes; when He has come, He will tell us all things:” and they themselves asked John, “Are you Elias, or the Prophet?” For the saying, as I said, prevailed, both that concerning the Christ and that concerning Elias, not however rightly interpreted by them.
For the Scriptures speak of two advents of Christ, both this that is past, and that which is to come; and declaring these Paul said, “The grace of God, that brings salvation, has appeared, teaching us, that, denying ungodliness and worldly lusts, we should live soberly, and righteously, and godly.” Behold the one, hear how he declares the other also; for having said these things, he added, “Looking for the blessed hope and appearing of our great God and Saviour Jesus Christ.” And the prophets too mention both; of the one, however, that is, of the second, they say Elias will be the forerunner. For of the first, John was forerunner; whom Christ called also Elias, not because he was Elias, but because he was fulfilling the ministry of that prophet. For as the one shall be forerunner of the second advent, so was the other too of the first. But the Scribes, confusing these things and perverting the people, made mention of that other only to the people, the second advent, and said, “If this man is the Christ, Elias ought to have come beforehand.” Therefore the disciples too speak as follows, “How then say the Scribes, Elias must first come?”
Therefore also the Pharisees sent unto John, and asked him, “Are you Elias?” making no mention anywhere of the former advent.
What then is the solution, which Christ alleged? “Elias indeed comes then, before my second advent; and now too is Elias come;” so calling John.
In this sense Elias has come: but if you would seek the Tishbite, he is coming. Wherefore also He said, “Elias truly comes, and shall restore all things.” All what things? Such as the Prophet Malachi spoke of; for “I will send you,” says He, “Elias the Tishbite, who shall restore the heart of father to son, lest I come and utterly smite the earth.”
Do you see the accuracy of prophetical language? How, because Christ called John, Elias, by reasoning of their community of office, lest you should suppose this to be the meaning of the prophet too in this place, He added His country also, saying, “the Tishbite;” whereas John was not a Tishbite. And herewith He sets down another sign also, saying, “Lest I come and utterly smite the earth,” signifying His second and dreadful advent. For in the first He came not to smite the earth. For, “I came not,” says He, “to judge the world, but to save the world.”
To show therefore that the Tishbite comes before that other advent, which has the judgment, He said this. And the reason too of his coming He teaches withal. And what is this reason? That when He has come, he may persuade the Jews to believe in Christ, and that they may not all utterly perish at His coming. Wherefore He too, guiding them on to that remembrance, says, “And he shall restore all things;” that is, shall correct the unbelief of the Jews that are then in being.
Hence the extreme accuracy of his expression; in that he said not, “He will restore the heart of the son to the father,” but “of the father to the son.” For the Jews being fathers of the apostles, his meaning is, that he will restore to the doctrines of their sons, that is, of the apostles, the hearts of the fathers, that is, the Jewish people's mind.
“But I say unto you, that Elias has come already, and they knew him not, but have done unto him whatsoever they listed. Likewise shall also the Son of Man suffer of them. Then they understood that He spoke to them of John.”
And yet neither the Scribes said this, nor the Scriptures; but because now they were sharper and more attentive to His sayings, they quickly caught His meaning.
And whence did the disciples know this? He had already told them, “He is Elias, which was for to come;” but here, that he has come; and again, that “Elias comes and will restore all things.” But be not thou troubled, nor imagine that His statement wavers, though at one time He said, “he will come,” at another, “he has come.” For all these things are true. Since when He says, “Elias indeed comes, and will restore all things,” He means Elias himself, and the conversion of the Jews which is then to take place; but when He says, “Which was for to come,” He calls John, Elias, with regard to the manner of his administration. Yea, and so the prophets used to call every one of their approved kings, David; and the Jews, “rulers of Sodom,” and “sons of Ethiopians;” because of their ways. For as the other shall be forerunner of the second advent, so was this of the first.
2. And not for this only does He call him Elias everywhere, but to signify His perfect agreement with the Old Testament, and that this advent too is according to prophecy.
Wherefore also He adds again, “He came, and they knew him not, but have done unto him all things whatsoever they listed.” What means, “call things whatsoever they listed?” They cast him into prison, they used him despitefully, they slew him, they brought his head in a charger.
“Likewise shall also the Son of Man suffer of them.” Do you see how again He in due season reminds them of His passion, laying up for them great store of comfort from the passion of John. And not in this way only, but also by presently working great miracles. Yea, and whenever He speaks of His passion, presently He works miracles, both after those sayings and before them; and in many places one may find Him to have kept this rule.
“Then,” for instance, it says, “He began to signify how that He must go unto Jerusalem, and be killed, and suffer many things.” “Then:” when? When He was confessed to be Christ, and the Son of God.
Again on the mountain, when He had shown them the marvellous vision, and the prophets had been discoursing of His glory, He reminded them of His passion. For having spoken of the history concerning John, He added, “Likewise shall also the Son of Man suffer of them.”
And after a little while again, when He had cast out the devil, which His disciples were not able to cast out; for then too, “As they abode in Galilee,” so it says, “Jesus said unto them, The Son of Man shall be betrayed into the hands of sinful men, and they shall kill Him, and the third day He shall rise again.”
Now in doing this, He by the greatness of the miracles was abating the excess of their sorrow, and in every way consoling them; even as here also, by the mention of John's death, He afforded them much consolation.
But should any one say, “Wherefore did He not even now raise up Elias and send him, witnessing as He does so great good of his coming?” we should reply, that even as it was, while thinking Christ to be Elias, they did not believe Him. For “some say,” such are the words, “that You are Elias, and others, Jeremias.” And indeed between John and Elias, there was no difference but the time only. “Then how will they believe at that time?” it may be said. Why, “he will restore all things,” not simply by being recognized, but also because the glory of Christ will have been growing more intense up to that day, and will be among all clearer than the sun. When therefore, preceded by such an opinion and expectation, he comes making the same proclamation as John, and himself also announcing Jesus, they will more easily receive his sayings. But in saying, “They knew him not,” He is excusing also what was done in His own case.
And not in this way only does He console them, but also by pointing out that John's sufferings at their hands, whatever they are, are undeserved; and by His throwing into the shade what would annoy them, by means of two signs, the one on the mountain, the other just about to take place.
Source: Homilies on the Gospel of St. Matthew (New Advent)