30 And their eyes were opened; and Jesus straitly charged them, saying, See that no man know it.
[AD 367] Hilary of Poitiers on Matthew 9:27-31
Or He enjoins silence on the blind men, because to preach was the Apostles' office.

[AD 407] John Chrysostom on Matthew 9:27-30
Wherefore can it be that He puts them off, and they crying out? Here again teaching us utterly to repel the glory that cometh from the multitude. For because the house was near, He leads them thither to heal them in private. And this is evident from the fact, that He charged them moreover to tell no man.

But this is no light charge against the Jews; when these men, though their eyes were struck out, receive the faith by hearing alone, but they beholding the miracles, and having their sight to witness what was happening, do all just contrary. And see their earnestness also, both by their cry, and by their prayer itself. For they did not merely approach Him, but with loud cries, and alleging nought else but "mercy."

And they called Him "Son of David," because the name was thought to be honorable. In many passages, for instance, did the prophets likewise so call the kings, whom they wished to honor, and to declare great.

And having brought them into the house, He puts to them a further question. For in many cases He made a point of healing on entreaty, lest any should suppose Him to be rushing upon these miracles through vainglory: and not on this account alone, but to indicate also that they deserve healing, and that no one should say, "If it was of mere mercy that He saved, all men ought to be saved." For even His love to man hath a kind of proportion; depending on the faith of them that are healed. But not for these causes only doth He require faith of them, but forasmuch as they called Him "Son of David," He to lead them up to what is higher, and to teach them to entertain the imaginations they ought of Himself, saith, "Believe ye that I am able to do this?" He did not say, "Believe ye that I am able to entreat my Father, that I am able to pray" but, "that I am able to do this?"

What then is their word? "Yea, Lord." They call Him no more Son of David, but soar higher, and acknowledge His dominion.

And then at last He for His part lays His hand upon them, saying, "According to your faith be it unto you." And this He doth to confirm their faith, and to show that they are participators in the good work, and to witness that their words were not words of flattery. For neither did He say, "Let your eyes be opened," but, "According to your faith be it unto you;" which He saith to many of them that came unto Him; before the healing of their bodies, hastening to proclaim the faith in their soul; so as both to make them more approved, and to render others more serious.

Thus with respect to the sick of the palsy also; for there too before giving nerve to the body, He raises up the fallen soul, saying, "Son, be of good cheer, thy sins be forgiven thee." And the young damsel too, when He had raised her up, He detained, and by the food taught her her Benefactor; and in the case of the centurion also He did in like manner, leaving the whole to his faith; and as to His disciples again, when delivering them from the storm on the sea, He delivered them first from their want of faith. Just so likewise in this case: He knew indeed, even before their cry, the secrets of their mind; but that He might lead on others also to the same earnestness, He makes them known to the rest as well, by the result of their cure proclaiming their hidden faith.

[AD 407] John Chrysostom on Matthew 9:30-31
Then after their cure He commands them to tell no man; neither doth He merely command them, but with much strictness.

"For Jesus," it is said, "straitly charged them, saying, See that no man know it. But they, when they were departed, spread abroad His fame in all that country."

They however did not endure this, but became preachers, and evangelists; and when bidden to hide what had been done, they endured it not.

And if in another place we find Him saying, "Go thy way, and declare the glory of God," that is not contrary to this, but even highly in agreement herewith. For He instructs us to say nothing ourselves, concerning ourselves, but even to forbid them that would eulogise us: but if the glory be referred to God, then not only not to forbid, but to command men to do this.

[AD 407] John Chrysostom on Matthew 9:27-31
(Hom. xxxii.) Here is no small charge against the Jews, that these men, having lost their sight, yet believe by means of their heaving only; while they who had sight, would not believe the miracles that were done. Observe their eagerness; they do not simply come to Him, but with crying, and asking for nothing but mercy; they call Him Son of David, because that seemed to be a name of honour.

Observe that the Lord oftentimes desired to be asked to heal, that none should think that He was eager to seize an occasion of display.

Here again He teaches us to exclude the desire of fame; because there was a house hard by, He takes them there to heal them apart.

And not for this reason only, but that He might make manifest that they were worthy of healing, and that none might object, that if mercy alone saved, then ought all to be saved. Therefore also He requires faith of them, that He may thereby raise their thoughts higher; they had called Him the Son of David, therefore He instructs them that they should think higher things of Him. Thus He does not say to them, Believe ye that I can ask the Father? But, Believe ye that I am able to do this? They say unto him, Yea, Lord. They call Him no more Son of David, but exalt Him higher, and confess His dominion. Then He lays His hand upon them; as it follows, Then he touched their eyes, saying, According to your faith be it unto you. This He says confirming their faith, and testifying that what they had said were not words of flattery. Then follows the cure, And their eyes were opened. And after this, His injunction that they should tell it to no man; and this not a simple command, but with much earnestness, And Jesus straitly charged them, saying, See that no man know it; but they went forth, and spread abroad the fame of him through the whole country.

That He said to another man, Go, and proclaim the glory of God, (Luke 8:39.) is not contrary to this; for what He would teach is, that we should hinder those that would commend us for ourselves. But when it is the Lord's glory that is to be praised, we ought not to forbid, but to promote it ourselves.

[AD 420] Jerome on Matthew 9:30-31
(Verse 30, 31.) And Jesus warned them, saying, "See that no one knows." But when they went out, they spread the news about him throughout that whole land. And the Lord, fleeing the glory of boastfulness because of his humility, had commanded this. And they, because of the remembrance of his grace, cannot remain silent about the kindness. Note, therefore, that something contrary to what was commanded must have happened. These blind men are healed in the tenth place.

[AD 420] Jerome on Matthew 9:27-31
The miracles that had gone before of the ruler's daughter, and the woman with the issue of blood, are now followed by that of two blind men, that what death and disease had there witnessed, that blindness might now witness. And as Jesus passed thence, that is, from the ruler's house, there followed him two blind men, crying, and saying, Have mercy on us, thou Son of David.

Let Marcion and Manichæus, and the other heretics who mangle the Old Testament, hear this, and learn that the Saviour is called the Son of David; for if He was not born in the flesh, how is He the Son of David?

Yet were they not healed by the way-side and in passing as they had thought to be; but when He was entered into the house, they come unto Him; and first their faith is made proof of, that so they may receive the light of the true faith. And when he was come into the house, the blind men came unto him; and Jesus said unto them, Believe ye that I am able to do this?

The Lord from humility shunning the fame of His glorious works, gave them this charge, and they from gratitude cannot be silent respecting so great benefit.

[AD 533] Remigius of Rheims on Matthew 9:27-31
Rightly they call Him Son of David, because the Virgin Mary was of the line of David.

He who was able to give sight to the blind, was not ignorant whether they believed; but He asked them, in order that the faith which they bare in their hearts, being confessed by their mouth might be made deserving of a higher reward, according to that of the Apostle, By the mouth confession is made unto salvation. (Rom. 10:10.)

Allegorically; By these two blind men are denoted the two nations of Jews and Gentiles, or the two nations of the Jewish race; for in the time of Roboam his kingdom was Split into two parts. Out of both nations such as believed on Him Christ gave sight to in the house, by which is understood the Church; for without the unity of the Church no man can be saved. And they of the Jews who had believed the Lord's coming spread the knowledge thereof throughout the whole earth.

[AD 604] Gregory the Dialogist on Matthew 9:27-31
(Mor. xix. 23.) We must enquire how this is that the Almighty, whose will and power are coextensive, should have here willed that His excellent works should be hid in silence, and is yet preached against His will, as it were, by these men who have received their sight. It is only that He herein has left an example to His servants who follow Him, that they should desire their own good deeds to be hid, and that notwithstanding they should be made known against their will, that others may profit by their example. They should then be hid by design, and published of compulsion; their concealment is by our own watchfulness, their betrayal is for others' profit.

[AD 856] Rabanus Maurus on Matthew 9:27-31
The maiden is raised in the house with few to witness, the young man without the gate, and Lazarus in the presence of many; for a public scandal requires a public expiation; a less notorious, a lesser remedy; and secret sins may be done away by penitence.

The house of the ruler is the Synagogue which was ruled by Moses; the house of Jesus is the heavenly Jerusalem. As the Lord passed through this world and was returning to His own house, two blind men followed Him; that is, when the Gospel was preached by the Apostles, many of the Jews and Gentiles began to follow Him. But when He ascended into Heaven, then He entered His house, that is, into the confession of one faith which is in the Catholic Church, and in that they were enlightened.

[AD 1107] Theophylact of Ohrid on Matthew 9:30
Do you see Christ's humility? They spread abroad His fame in thanksgiving, not out of disobedience. But if in another place Christ says, Go and tell of the glory of God [Lk.8:39], there is nothing contradictory in this. For He wants them to say nothing about Himself, but to speak of the glory of God.