The interpretation timeline
Matthew 1:19 Douay-Rheims

Whereupon Joseph her husband, being a just man, and not willing publicly to expose her, was minded to put her away privately.

A.D. 253 – 1871 12 witnesses 16 excerpts

Patristic

before A.D. 750
253
A.D.
Origen Patristic
c. A.D. 184–253
“But if he had no suspicion of her, how could he be a just man, and yet seek to put her away, being immaculate? He sought, to put her away, because he saw in her a great sacrament, to approach which he thought himself unworthy.”
397
A.D.
Ambrose of Milan Patristic
A.D. 339–397
“(in Luc. ii. 5.) St. Matthew has beautifully taught how a righteous man ought to act, who has detected his wife’s disgrace; so as at once to keep himself guiltless of her blood, and yet pure from her defilements; therefore it is he says, Being a just man. Thus is preserved throughout in Joseph the gracious character of a righteous man, that his testimony may be the more approved; for, the tongue of the just speaketh the judgment of truth.”
Source
“(in Luc. ii. 1.) But as no one puts away what he has not received; in that he was minded to put her away, he admits to have received her.”
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“The Evangelist having said that she was found with child of the Holy Ghost, and without knowledge of man, that you should not herein suspect Christ’s disciple of inventing wonders in honour of his Master, brings forward Joseph confirming the history by his own share in it; Now Joseph her husband, being a just man.”
“But it should be known, that just here is used to denote one who is in all things virtuous. For there is a particular justice, namely, the being free from covetousness; and another universal virtue, in which sense Scripture generally uses the word justice. Therefore being just, that is kind, merciful, he was minded to put away privily her who according to the Law was liable not only to dismissal, but to death. But Joseph remitted both, as though living above the Law. For as the sun lightens up the world, before he shews his rays, so Christ before He was born caused many wonders to be seen.”
Source
420
A.D.
Jerome Patristic
c. A.D. 347–420
“But how is Joseph thus called just, when he is ready to hide his wife’s sin? For the Law enacts, that not only the doers of evil, but they who are privy to any evil done, shall be held to be guilty.”
“Or this may be considered a testimony to Mary, that Joseph, confident in her purity, and wondering at what had happened, covered in silence that mystery which he could not explain.”
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“Otherwise; if you alone have knowledge of a sin that any has committed against you, and desire to accuse him thereof before men, you do not herein correct, but rather betray him. But Joseph, being a just man, with great mercy spared his wife, in this great crime of which he suspected her. The seeming certainty of her unchastity tormented him, and yet because he alone knew of it, he was willing not to publish it, but to send her away privily; seeking rather the benefit than the punishment of the sinner.”
Source

Medieval

c. 750 – 1100
856
A.D.
Rabanus Maurus Medieval
c. A.D. 780–856
“He beheld her to be with child, whom he knew to be chaste; and because he had read, There shall come a Rod out of the stem of Jesse, (Is. 11:1.) of which he knew that Mary was comes, and had also read, Behold, a virgin shall conceive, (Is. 7:14.) he did not doubt that this prophecy should be fulfilled in her.”

Scholastic

c. 1100 – 1500
1256
A.D.
Thomas Aquinas Catholic
1225–1274
“"And she shall bring forth a son." Here he foretells the service that Joseph will render to the child now born, and he does three things: first he foretells the Virgin's childbearing; second he shows in advance the service to be rendered by Joseph himself to the child, when he says "and you shall call his name"; third he discloses the name imposed upon the child himself, when he says "Jesus." He says therefore "she shall bring forth." Thus she conceived of the Holy Spirit indeed first, but she shall bring forth a son. He does not say "to you," because he himself did not beget the child. In Luke 1:13 it was said to Zachary: "your wife shall bear you a son," because Zachary himself begot him. Or he does not say "to you" for this reason, that it may be shown that he was born for all: not only to you, or to her, shall she bring forth a son, but to the whole world; Luke 2:10: "behold, I announce to you a great joy, for there is born to you this day a Savior, who is Christ the Lord, in the city of David," and so on. But because Joseph could say: thus she herself conceived of the Holy Spirit, and shall bring forth a son, what then is this to me? In nothing am I necessary to him. Therefore he adds Joseph's own service: "you shall call his name." It was the custom among the Hebrews, and is so today, that on the eighth day they circumcised the child, and then imposed a name upon him; and this was done through Joseph: hence in this work he was the minister. Hence it is said to him "you shall call"; it is not said "you shall impose," because it is already imposed upon him; Isaiah 62:2: "a new name shall be called to you, which the mouth of the Lord has named." "Jesus" — this is the name imposed by God. And he gives the reason: "for he himself shall make his people safe," whom he acquired for himself by his own blood, that is, his people. Daniel 9:26 it is said: "the people shall not be his, who is about to deny him"; hence it is the people of the Lord through faith; 1 Peter 2:9: "you are a chosen race, a royal priesthood, a holy nation, a people of acquisition." "From their sins." In the book of Judges it is frequently said that such and such a one saved Israel: but from whom? From carnal enemies; but here, from sins, by remitting sins, which belongs to God alone. Luke 5:24: "but that you may know that the Son of Man has power on earth to forgive sins." Note that here Nestorius is confounded, who said that those things which belong to God, such as being from eternity, being omnipotent, or the like, do not belong to that man. Behold, that same man, who was born of the Virgin, who is called Jesus, he himself shall make his people safe from their sins. Hence, since no one can forgive sins except God alone, it must be said that this man is God, and that the things which belong to God most truly belong to him. The Evangelist had said beforehand that the mother of God was found to have in her womb one conceived of the Holy Spirit, and this he proved above through angelic revelation; here he proves it through the foretelling of prophecy; hence he says: "all this was done that it might be fulfilled which was spoken by the Lord through the prophet." And it must be known that this clause can be introduced here in two ways. Chrysostom holds that the Angel said all this and introduced the prophecy. And the reason is that he, lest what he was foretelling should seem new, wished to show at once that it had been foretold of old; Isaiah 48:3: "who has already made what is to come," according to another translation. Others say, and I believe it is better, that this, namely "all this was done," etc., are the words of the Evangelist. For there the words of the Angel end: "and he himself shall make [his people] safe," and so on. And the Evangelist introduces them for three reasons. First, that he might show that the Old Testament is about Christ; Acts 10:43: "to him all the prophets give testimony, that all who believe in him receive remission of sins through his name." Second, that they might more easily believe Christ: John 5:46: "if you believed Moses, you would perhaps believe me also: for he wrote of me." Third, to show the conformity of the Old and New Testament; Colossians 2:17: "which are a shadow of things to come, but the body is Christ's." But so that it may be known what is contained in this prophecy, it must be known that the Angel announces three things. First he said "that which is born in her," etc.; second, "she shall bring forth a son"; third, "his name shall be called Jesus." These are contained in order in the prophecy. And the first he proves by what is said, "behold the virgin"; second, by "and she shall bring forth"; third, by "and shall be called." Therefore it was of the Holy Spirit that she conceived through virginity. And this is what is said in the prophecy, "behold a virgin shall conceive"; Isaiah 35:2: "budding it shall bud forth, and shall rejoice with joy, and praising," and so on. Likewise the virgin shall bring forth a son, because in bringing forth her virginity was in no way harmed; Isaiah 11:1: "a rod shall come forth from the root of Jesse, and a flower shall rise from its root," and so on. Christ indeed is the flower. Therefore her virginity was in no way harmed. There follows: "and his name shall be called Emmanuel." But it is asked, why does this not agree with the words of the Angel, who says "and he shall be called Jesus"? It must be said that this promise was made to the Jews, who from the coming of Christ would have salvation. And "Jesus" is interpreted "savior," which is the same as Emmanuel, "God with us." For God is with us in four ways: through the assumption of nature, John 1:14: "the Word was made flesh"; through conformity of nature, since he is like in all things, Philippians 2:7: "made in the likeness of men, and found in habit as a man"; through bodily conversation, Baruch 3:38: "afterward he was seen upon the earth, and conversed with men"; through spiritual conversation, below, at the end, [Matthew] 28:20: "behold I am with you all days, even to the consummation of the world." But it must be asked, concerning the letter, why the Evangelist does not use the same words as the prophet, but uses the name Jesus. It must be said that he spoke by the same Spirit. Yet Jerome says that the Evangelist therefore said "would have," because he was already speaking of the fact as accomplished. Likewise it must be asked, why in Isaiah it is said "and he shall be called," but here it is said "and they shall call." Jerome says that here it is said "they shall call," because what the Angels first called by announcing, Luke 2:21, afterward the apostles called by preaching and magnifying; "that in the name of Jesus every knee should bow," etc., Philippians 2:10. "Which is interpreted, God with us." But it is asked, who appended this interpretation to the prophecy, "God with us" — the prophet, or the Evangelist? And it seems that it was not the Evangelist, because he did not need this, since he wrote in Hebrew. But it must be said, in one way, that because Emmanuel is a composite name, therefore the Evangelist interpreted it even though writing in Hebrew. Or it must be said that he who first translated from the Hebrew provided the interpretation. And it must be noted that in the Gloss it is said that there is a threefold species of prophecy, namely of predestination, of foreknowledge, and of threat; and they differ. For prophecy is called the foretelling of those things which are far off, that is, of future things; but of future things, some are such that God alone does them; some indeed, although God does them, nevertheless come about through us and through other creatures as well; and some are such that God does them in no way at all, as evils. The foretelling of those things which God alone does is called the prophecy of predestination, as the conceiving of the virgin; hence that saying, Isaiah 7:14: "behold a virgin shall conceive," is a prophecy of predestination. But those things which come about from secondary causes can be considered in two ways. First, according as they are in the foreknowledge of God — for example concerning Lazarus; for if someone were to consider the natural causes, he would say that he would never rise, and he would speak truly: although nevertheless he was to be raised according to the order of divine foreknowledge. Therefore when prophecy is a foretelling according as it is in the divine foreknowledge, it is always fulfilled; but when according to the order of lower causes, not always, as is clear in Isaiah 38:1, when Isaiah said to Hezekiah: "set your house in order, for you shall die, and not live," and so on. But does prophecy impose necessity on foreknowledge? And it must be said that it does not; because prophecy is a certain sign of divine foreknowledge, which does not impose necessity on the things foreknown, because it considers future things in their presentness. For whatever is done is present to God, because his gaze extends to every time; for if I see something present, my gaze does not impose necessity, just as when I see someone sitting. And in this way we have understood these prophecies which are introduced in this book. For it must be considered that there have been three errors. One is that of the Manichees, who say that in the whole Old Testament no prophecy about Christ is found: and whatever is brought in from the Old into the New Testament is entirely due to corruption. Against which, Romans 1:1: "Paul, a servant of Christ, called an apostle, set apart unto the Gospel of God, which he had promised before through his prophets," and so on. And that he speaks of the prophecies of the Jews is clear below, at chapter 9:5 [Romans 9:5]: "whose are the fathers, of whom is Christ according to the flesh," and so on. The other was that of Theodore, who said that none of the things which are brought in from the Old Testament are, according to the letter, about Christ, but are adapted, just as when they bring in that line of Virgil, "such things he recalled hanging, and remained fixed" — for this is adapted to Christ; and then that phrase "that it might be fulfilled" ought to be expounded thus, as if the Evangelist were saying: "and this can be adapted." Against which, Luke, the last chapter, 44 [Luke 24:44]: "all things must be fulfilled which are written in the law of Moses, and the prophets, and the Psalms concerning me." And it must be known that in the Old Testament there are some things which are referred to Christ, and are said of him alone, as that saying, "behold a virgin shall conceive in the womb, and bring forth a son," Isaiah 7:14; and that saying, Psalm 21:2 [Psalm 22:2]: "God, my God, look upon me, why have you forsaken me?" and so on. And if anyone were to posit another literal sense, he would be a heretic, and the heresy has been condemned. But because not only the words of the Old Testament, but also the deeds signify concerning Christ, sometimes certain things are said according to the letter about certain others, but are referred to Christ, insofar as those others bear the figure of Christ, as it is said of Solomon: "and he shall have dominion from sea to sea," etc.; for this was not fulfilled in him. The third error was that of the Jews. It must be known, however, that the Jews especially object against this authority, because in the Hebrew it does not have "virgin," but "alma," which is the same as "young girl." Hence, according to the letter, these things are not said of Christ but of Emmanuel, or, according to others, of a certain son of Isaiah. But Jerome objects against these; and that it could not have been said of the son of Isaiah is proved, because he was already born when this was said. Likewise, no one is found to have been famous at that time who was called Emmanuel. Likewise, it is not a sign that a young woman should give birth. Hence Jerome says that "alma" is an equivocal word, and signifies sometimes age, sometimes "hidden," and then it signifies a virgin diligently kept; and thus it signifies here. Likewise the Jews object that this was given as a sign. Isaiah 7:3: "two kings shall come against Achaz," etc., and he promised that they would be freed from these by giving this sign to Achaz. But it must be said that he gave this sign not only to Achaz, but also to the house of David, because he says, "hear then, O house of David"; as if the prophet were saying: the Lord will help you against this king, because he himself will do much greater things, since there will be liberation not only of him, but of the whole world. But let us return to the letter. "All this was done." But against this: the Angel had said many things beforehand, namely that "that which is born in her," etc., "she shall bring forth," etc., and again, "he shall be called," and so on. But this had not all yet been done. But it must be said, in one way, according to Rabanus, that "all this was done," etc., is referred to past deeds — that the Angel appeared to the Virgin, and spoke those words — and "all this was done" for the preserving of the Virgin, so that the word "that" is taken causally. Or it is referred to the things which he had foretold; and it can be called "wholly done" on account of predestination. Or it must be said that the Evangelist was writing when it had all already been done; and therefore it refers to that. Hence the word "that" is taken consecutively, because God did not will to become incarnate for this reason, that the prophecy might be fulfilled, as though the Old Testament were more worthy than the New; but this, that Christ should become incarnate, followed upon the prophecy.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“Then Joseph her husband,.... To whom she had been betrothed, and who was her husband, and she his wife according to the Jewish law, Deu 22:23 though not yet come together, being a just man, observant of the law of God, particularly that which respected adultery, being wholly good and chaste, like the Patriarch of the same name; a character just the reverse of that which the Jews give him, in their scandalous (b) book of the life of Jesus; where, in the most malicious manner, they represent him as an unchaste and an unrighteous person: and not willing to make her a public example, or to deliver her, i.e. to the civil magistrate, according to Munster's Hebrew edition. The Greek word signifies to punish by way of example to others, to deter them from sinning; and with the ancients it (c) denoted the greatest and severest punishment. Here it means either bringing her before the civil magistrate, in order to her being punished according to the law in Deu 22:23 which requires the person to be brought out to the gate of the city and stoned with stones, which was making a public example indeed; or divorcing her in a very public manner, and thereby expose her to open shame and disgrace. To prevent which, he being tender and compassionate, though strictly just and good, was minded to put her away privily: he deliberately consulted and determined within himself to dismiss her, or put her away by giving her a bill of divorce, in a very private manner; which was sometimes done by putting it into the woman's hand or bosom, see Deu 24:1. In Munster's Hebrew Gospel it is rendered, "it was in his heart to forsake her privately." (b) Teldos Jesu, p. 3. (c) A. Gellii Noct. Attic. l. 6. c. 14.”
Source
1849
A.D.
1774–1849
“And Joseph her husband, knowing her strict virtue, was surprised at this her pregnancy, but “being a just man,” and not willing to expose her, by denouncing her, or giving her a bill of divorce, he had a mind to dismiss her privately, committing the whole cause to God. Let us learn from Joseph to be ever tender of our neighbour’s reputation, and never to entertain any injurious thoughts, or any suspicions to his prejudice. (Haydock)”
Source
1871
A.D.
1871
“Then Joseph her husband--Compare Mat 1:20, "Mary, thy wife." Betrothal was, in Jewish law, valid marriage. In giving Mary up, therefore, Joseph had to take legal steps to effect the separation. being a just man, and not willing to make her a public example--to expose her (see Deu 22:23-24) was minded to put her away privily--that is, privately by giving her the required writing of divorcement (Deu 24:1), in presence of only two or three witnesses, and without cause assigned, instead of having her before a magistrate. That some communication had passed between him and his betrothed, directly or indirectly, on the subject, after she returned from her three months' visit to Elizabeth, can hardly be doubted. Nor does the purpose to divorce her necessarily imply disbelief, on Joseph's part, of the explanation given him. Even supposing him to have yielded to it some reverential assent--and the Evangelist seems to convey as much, by ascribing the proposal to screen her to the justice of his character--he might think it altogether unsuitable and incongruous in such circumstances to follow out the marriage.”
Source

Undated

date unknown
date
unknown
“(Serm. in App. s. 195.) Joseph, understanding that Mary was with child, is perplexed that it should be thus with her whom he had received from the temple of the Lord, and had not yet known, and resolved within himself, saying, What shall I do? Shall I proclaim it, or shall I overlook it? If I proclaim it, I am indeed not consenting to the adultery; but I am running into the guilt of cruelty, for by Moses’ law she must be stoned. If I overlook it, I am consenting to the crime, and take my portion with the adulterers. Since then it is an evil to overlook the thing, and worse to proclaim the adultery, I will put her away from being my wife.”
Source
date
unknown
Glossa Ordinaria Medieval
“(ap. Anselm.) Or, in seeking to put her away, he was just; in that he sought it privily, is shewn his mercy, defending her from disgrace; Being a just man, he was minded to put her away; and being unwilling to expose her in public, and so to disgrace her, he sought to do it privily.”
“(part ap. Anselm. part in Ord.) Or, being unwilling to bring her home to his house to live with him for ever, he was minded to put her away privily; that is, to change the time of their marriage. For that is true virtue, when neither mercy is observed without justice, nor justice without mercy; both which vanish when severed one from the other. Or he was just because of his faith, in that he believed that Christ should be born of a virgin; wherefore he wished to humble himself before so great a favour.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.