The interpretation timeline
John 10:9 Douay-Rheims

I am the door. By me, if any man enter in, he shall be saved: and he shall go in, and go out, and shall find pastures.

A.D. 430 – 1871 8 witnesses 9 excerpts

Patristic

before A.D. 750
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“(Tr. xlv. 8) Understand, All that ever came at variance with Me. The Prophets were not at variance2 with Him. They came with Him, who came with the Word of God, who spake the truth. He, the Word, the Truth, sent heralds before Him, but the hearts of those whom He sent were His own. They came with Him, inasmuch as He is always, though He assumed the flesh in time: In the beginning was the Word. His humble advent in the flesh was preceded by just men, who believed on Him as about to come, as we believe on Him come. The times are different, the faith is the same. Our faith knitteth together both those who believed that He was about to come, and those who believe that He has come. All that ever came at variance with Him were thieves and robbers; i. e. they came to steal and to kill; but the sheep did not hear them. They had not Christ’s voice; but were wanderers, dreamers, deceivers. Why He is the Door, He next explains, I am the Door; by Me if any man enter in he shall be saved.”
Source
604
A.D.
Gregory the Great Patristic
c. A.D. 540–604
“(super Ezek. Hom. xiii.) Shall go in, i. e. to faith: shall go out, i. e. to sight: and find pasture, i. e. in eternal fulness.”

Scholastic

c. 1100 – 1500
1107
A.D.
c. 1055–1107
“The door admits the sheep into the pasture; And shall go in and out, and find pasture. What is this pasture, but the happiness to come, the rest to which our Lord brings us?”
“Or, to go in is to watch over the inner man; to go out, (Colos. 3) to mortify the outward man, i. e. our members which are upon the earth. He that doth this shall find pasture in the life to come.”
1270
A.D.
Thomas Aquinas Catholic
1225–1274
“Here he expounds the second clause of the aforementioned parable, namely, he who enters through the door is the shepherd of the sheep, and first he sets forth the exposition; second he makes it clear, at the place I am the good shepherd, and so on. He expounds that particular point by saying that he himself is the good shepherd: second, he subjoins the office of the good shepherd, at the place the good shepherd gives his life for his sheep; third, he shows the contrary concerning the bad shepherd, at the place but the hireling ... sees the wolf coming, and flees. He says therefore, as to the first point, I am the good shepherd. That Christ is a shepherd manifestly belongs to him: for just as through a shepherd the flock is governed and fed, so the faithful are refreshed by Christ with spiritual food, and also with his own body and blood; 1 Peter 2:25: "You were once like sheep having no shepherd, but you have now been converted to the shepherd and bishop of your souls"; Isaiah 40:11: "as a shepherd he will feed his flock." But to distinguish him from the bad shepherd and the thief, he adds good. Good, I say, because he fulfills the office of shepherd, just as a good soldier is called one who fulfills the office of a soldier. But since Christ had said above that the shepherd enters through the door, and again that he himself is the door, and here he says that he is the shepherd, it must be that he himself enters through himself. And indeed he enters through himself, because he manifests himself, and through himself he knows the Father. But we enter through him, because through him we are made blessed. But note that no one else is the door except him, because no one else is the true light, but only by participation; above, John 1:8: "he was not the light," namely John the Baptist, "but that he might bear witness to the light." But of Christ it is said, "he was the true light which enlightens every man." And therefore no one calls himself the door: this Christ himself kept properly for himself; but being a shepherd he communicated to others, and gave to his members: for Peter too was a shepherd, and the rest of the apostles were shepherds, and all good bishops; Jeremiah 3:15: "I will give you shepherds according to my own heart." But although the prelates of the Church, who are sons, are all shepherds, as Augustine says; nevertheless he says in the singular I am the good shepherd, in order to insinuate the power of charity. For no one is a good shepherd unless through charity he is made one with Christ, and becomes a member of the true shepherd. The office of the good shepherd is charity; hence he says, the good shepherd gives his life for his sheep. For it must be known that there is a difference between the good shepherd and the bad: for the good shepherd intends the advantage of the flock; but the bad one intends his own advantage: and this difference is touched on at Ezekiel 34:2: "Woe to the shepherds who feed themselves. Should not the flocks be fed by the shepherds?" He therefore who uses the flock only to feed himself is not a good shepherd. From which it follows that the bad shepherd, even a bodily one, wishes to sustain no loss for the flock, since he does not intend their advantage, but his own. But the good shepherd, even a bodily one, sustains many things for the flock, whose good he intends; hence Jacob said, Genesis 31:40: "by night and day I was burned with frost and heat." But in the case of bodily shepherds, it is not required of the good shepherd that he expose himself to death for the safety of the flock. But because the safety of the spiritual flock outweighs the bodily life of the shepherd, therefore when danger threatens the safety of the flock, every spiritual shepherd ought to sustain the loss of his bodily life for the safety of the flock. And this is what the Lord means when he says the good shepherd his life, that is, his bodily life, lays down for his sheep, that is, by authority and by charity. For both are required: both that they pertain to him, and that he loves them: for the first without the second does not suffice. Of this teaching Christ furnished us an example; 1 John 3:16: "if Christ laid down his life for us, we also ought to lay down our lives for the brethren." Here he treats of the bad shepherd, showing that conditions contrary to the conditions of the good shepherd are present in him; and first he sets forth the conditions of the bad shepherd; second he shows how these conditions follow one from another, at the place but the hireling ... flees. Concerning the first he does two things. First he sets forth the conditions of the bad shepherd; second he insinuates the danger threatening the flock from the bad shepherd, at the place and the wolf snatches, and so on. It should be noted that from what has been said about the good shepherd and what is said about the bad one, a threefold difference of their conditions, namely of the good and the bad shepherd, can be gathered. The first distinction indeed is taken as to intention; the second as to affection; the third as to solicitude. They differ therefore first in intention, and this from the name of each: for the first is called shepherd, from which it is given to be understood that he intends to feed the flock; Ezekiel 34:2: "should not the flocks be fed by the shepherds?" But the other, namely the bad one, is called a hireling, as it were seeking wages. So that they differ in this: that the good shepherd seeks the benefit of the flock; but the hireling more principally his own advantage. This is also the difference between a king and a tyrant, as the Philosopher says, because a king in his rule intends the benefit of his subjects; but a tyrant his own benefit; hence he is like a hireling: Zechariah 11:12: "if it is good in your eyes, bring me my wages." But can even good shepherds seek wages? It seems that they can; Ecclesiasticus 36:18: "give a reward, Lord, to those who wait for you"; Isaiah 40:10: "behold his reward is with him"; and Luke 15:17: "how many hired servants in my father's house have abundance of bread." I respond. It must be said that "wages" can be taken in two ways: namely, commonly and properly. Commonly indeed, everything that is rendered for merits is called wages, and because eternal life, which is God — 1 John, last chapter, 20: "this is the true God, and eternal life" — is rendered for merits, therefore eternal life itself is called wages. And this wage every good shepherd can and ought to seek. But properly, wages is said of something separated from an inheritance; and he who is a true son, to whom the inheritance belongs, ought not to have regard to this; but servants and hirelings have regard to it. Hence, since eternal life is our inheritance, whoever works having regard to it works as a son; but whoever intends something apart from it (for instance, gapes after earthly advantages, rejoices in the honor of prelacy) is a hireling. Second, they are distinguished as to solicitude: because of the good shepherd it is said that the sheep are his own, not only by commission, but also by love and solicitude; Philippians 1:7: "because I have you in my heart," etc.; but of the hireling it is said whose own the sheep are not, that is, he has no solicitude for them; Ezekiel 34:8: "neither have the shepherds sought my flock, but they fed themselves." Third, they differ as to affection: for the good shepherd, who loves the flock, gives his life for it, that is, exposes himself to the danger of bodily life. But the bad one, because he has no affection for the flock, flees when he sees the wolf. Hence he says he sees the wolf coming, and abandons the sheep. This wolf is understood in three ways. First indeed, the devil tempting; Ecclesiasticus 13:21: "but if ever the wolf had fellowship with the lamb, so the sinner with the just man." Second, the heretic slaughtering; Matthew 7:15: "beware of false prophets, who come to you in the clothing of sheep"; Acts 20:29: "I know that after my departure ravening wolves will enter in among you, not sparing the flock." Third, the raging tyrant: Ezekiel 22:27: "her princes in the midst of her are like wolves." The good shepherd, therefore, ought to protect his subject flock against this threefold wolf: namely, when, seeing the wolf — that is, diabolical temptation, heretical deception, and tyrannical savagery — he opposes himself: against which it is said, Ezekiel 13:5: "you have not gone up to face the enemy, nor have you set up a wall for the house of Israel." And therefore it is said of the bad shepherd that he flees and abandons the sheep; Zechariah 11:17: "O shepherd, and idol, forsaking the flock"; as if to say: you are not a shepherd, but you bear the likeness and idol of a shepherd; Jeremiah 46:21: "her hirelings also in the midst of her are like fatted calves, and they too are turned back, and are fled away together, and they stood not." But against this is what is said at Matthew 5:11: "if they persecute you in one city, flee into another." Therefore it seems that it is lawful for a shepherd to flee. I respond. It must be said that there is a twofold solution to this. One is Augustine's, on John. For there is a twofold flight: namely, of the mind and of the body. But what is said here, he abandons the sheep and flees, is understood of the flight of the mind: for while the bad shepherd fears danger to himself from the wolf, he does not presume to resist its injustice; but he flees not by changing place, but by withdrawing comfort, shrinking, that is, from solicitude for the flock. But this exposition is necessary as regards the first wolf, for against the devil one need not flee bodily. But because it also happens that some shepherd flees bodily on account of certain wolves, namely a heretic having power, and a tyrant, therefore another answer must be applied, which Augustine gives in his letter to Honoratus. For, as he himself says, it seems that it is lawful even to flee the wolves bodily, not only from the authority of the Lord set forth above, but also from the example of certain saints, for instance Athanasius and others who fled their persecutors. For he is blamed not because he flees, but because he abandons the sheep: hence if he could flee without abandoning the sheep, it would not be blameworthy. For it happens sometimes that the person of the prelate is sought; sometimes the whole flock. It is manifest, however, that if only the person of the prelate is sought, others can be deputed in his place to the custody of the flock, who in his stead may console and govern the flock. Hence if he flees in this way, he is not said to abandon the sheep; and in this manner, in such a case, it is lawful to flee. But if the whole flock is sought, either it is necessary that all the shepherds be together with the sheep, or it is necessary that some of them remain, and some withdraw. But if they totally desert the flock, then what is said here applies to them: he sees the wolf coming, and abandons the sheep, and flees. Here the imminent danger is set forth, which is twofold. One is the plundering of the sheep; hence he says the wolf snatches, that is, he usurps to himself what is another's. For the faithful of Christ are his sheep. Then, therefore, some heresiarch and wolf snatches the sheep, when he draws the faithful of Christ to his own false doctrine; Ezekiel 34:5: "my flock has become a prey to all the beasts of the field." The other danger is the dispersion of the sheep, hence he says and scatters the sheep, inasmuch as some are led astray, and some persist; Ezekiel 34:6: "my flocks have been scattered; and there was none to seek them." Here he shows how the aforesaid conditions follow one from another: for from the first two the third follows. For from the fact that he seeks his own advantage, and is not affectively disposed toward the flock through love and solicitude, it follows that he does not wish to sustain hardship for it. And therefore he says but the hireling flees, for this reason, namely, because he is a hireling, that is, he seeks his own advantage, as to the first condition; and it does not pertain to him concerning the sheep, that is, he does not love them, nor is he solicitous for them, as to his second condition. Hence at Job 39:16 it is said of the bad shepherd: "he is hardened toward his young as if they were not his own." But conversely it is with the good shepherd: for he seeks the advantage of the flock, not his own; Philippians 4:17: "I seek not the gift, but I seek the fruit," etc. And it pertains to him concerning the sheep; that is, he loves them, and is solicitous for them, Philippians 1:7: "because I have you in my chains," etc.”

Reformation

c. 1500 – 1650
1637
A.D.
1567–1637
“I am the door % &c. Rupertus thinks that this relates to a different door and a different sheepfold from the other, according to what b said (ver. 16), “Other sheep I have,” &c But there is only one fold of Christ ; one Church, that is. As He subjoins, “ There shall be one fold and one shepherd.” The meaning of the door already spoken of, Christ partly confirms, partly explains when He adds, “ By Me if any man enter in, he shall be saved.” That is, if any man believe in Me, and therefore through faith in Me and by My grace enters the Church, “ he shall be saved,” £*., shall be justified and blessed, if he continues, that is, in My faith, grace and charity even unto death. So S. Gregory ( EpisL lib . vii. 49). “ He enters through the door into the sheepfold who enters through Christ But he enters through Christ who believes and teaches the truth concerning Him — the Creator and Redeemer of mankind, and abides by what he preached.” And will go in and out . Will go out to the pastures, and after having fed will return to the resting-place, as sheep do. For the faithful will, when well fed, enter the fold of the Church, and again when hungry will go forth to the pastures of the soul, without any peril, for I will guide them to and fro. So Maldonatus. But to go in and out signifies among the Hebrews to act with freedom, do one's own work, &c., and b connected with what follows. It means, the faithful man will move about everywhere without fear ; will do hb duty, and whatever he does, whether at home or abroad, will everywhere find food for hb soul. The phrase denotes security, confidence, and freedom of converse; and of doing everything, everywhere, for and through Christ. So Cyril, Chrysostom. Symbolically and tropologically, S. Gregory ( Horn . xiv.) “ The faithful withdraws within himself by contemplation, and comes forth in action to do good works.” “ He will enter in,” says S. Augustine, “for inward meditation, he will go forth for outward action.” The author of De spiritu et anima, says, “ He will enter within to contemplate My Godhead, he will go forth to contemplate My Manhood, and in either case will find wondrous pastures.” And in Digitized by V^rOOQie WHO IS A THIEF. 365 another place S. Gregory writes, “ Within, they have the pastures of contemplation ; without, the pastures of good works ; inwardly they enrich their mind with devotions, outwardly they satiate themselves with good works.” And lastly, Theophylact says, “ He will enter in who has a care for the inward man ; he will go out who mortifies his members upon earth.” Anagogically, Rupertus says, “He enters the Church by faith, to find therein pastures ; he will go out when at death he migrates therefrom into heaven.” “He enters,” says S. Augustine, “into the Church through the door of faith, and goes forth through the same door of living faith into eternal life, where he will find pasture.” And S. Gregory, “He will enter into faith, he will go forth to hope, and will find pasture in eternal satiety.””
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“I am the door,.... Of the sheep, as before, see Joh 10:7. The Ethiopic version reads, "I am the true door of the sheep"; which is repeated for further confirmation, and for the sake of introducing what follows: by me if any man enter in; into the sheepfold, the church, he shall be saved; not that being in a church, and having submitted to ordinances, will save any, but entering into these, at the right door, or through faith in Christ, such will be saved, according to Mar 16:16; such shall be saved from sin, the dominion of it, the guilt and condemning power of it, and at last from the being of it; and from the law, its curse and condemnation, and from wrath to come, and from every evil, and every enemy; such are, and for ever shall be, in a safe state, being in Christ, and in his hands, out of which none can pluck them: and shall go in and out; in allusion to the sheep going in and out of the fold: not that those who come in at the right door, shall go out of the church, or from among the saints again; but this phrase rather denotes the exercises of faith in going unto Christ, and acting upon him, and in coming forth in the outward confession of him, and the performance of good works; or in going unto him, and dealing with his blood, righteousness, and sacrifice, and coming out of themselves, and all dependence on their own righteousness; or it may regard the conversation of the saints in the church, their attendance on ordinances, their safety there, their free and open communion one with another, and with Christ, in whose name and strength they do all they do, coming in and out at this door: and find pasture; green and good pasture; pasture for their souls; the words of faith, and good doctrine; the wholesome words of Christ Jesus; the ordinances, the breasts of consolation; yea, Christ himself, whose flesh is meat indeed, and whose blood is drink indeed: the Persic version renders it, "and shall a pastor", or "shepherd"; see Jer 3:15.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“I am the door: by me if any man enter, etc. - Those who come for salvation to God, through Christ, shall obtain it: he shall be saved - he shall have his sins blotted out, his soul purified, and himself preserved unto eternal life. This the scribes and Pharisees could neither promise nor impart. Go in and out - This phrase, in the style of the Hebrews, points out all the actions of a man's life, and the liberty he has of acting, or not acting. A good shepherd conducts his flock to the fields where good pasturage is to be found; watches over them while there, and brings them back again and secures them in the fold. So he that is taught and called of God feeds the flock of Christ with those truths of his word of grace which nourish them unto eternal life; and God blesses together both the shepherd and the sheep, so that going out and coming in they find pasture: every occurrence is made useful to them; and all things work together for their good.”
Source
1871
A.D.
1871
“by me if any man enter in--whether shepherd or sheep. shall be saved--the great object of the pastoral office, as of all the divine arrangements towards mankind. and shall go in and out and find pasture--in, as to a place of safety and repose; out, as to "green pastures and still waters" (Psa 23:2) for nourishment and refreshing, and all this only transferred to another clime, and enjoyed in another manner, at the close of this earthly scene (Rev 7:17).”
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.