The interpretation timeline
Isaiah 54:15 Douay-Rheims

Behold, an inhabitant shall come, who was not with me, he that was a stranger to thee before, shall be joined to thee.

1105 – 1871 5 witnesses

Scholastic

c. 1100 – 1500
1105
A.D.
Rashi Jewish
1040–1105
“Behold, the one with whom I am not, shall fear Heb. גּוֹר יָגוּר. Behold, he shall fear and dread evil decrees, he with whom I am not, i.e., Esau. ([Mss. read:] the wicked Esau and his ilk.) whoever mobilizes against you Heb. גָר. Whoever mobilizes against you for war. Alternatively, מִי גָר [means:] whoever contends with you (וְנִתְגָּרֶה). And our Rabbis explained it as referring to the proselytes (גֵּרִים), [i.e.,] to say that we will not accept proselytes in Messianic times. And even according to the simple meaning of the verse it is possible to explain: whoever became sojourners with you in your poverty, shall dwell with you in your wealth. Comp. (Gen. 25:18) “In the presence of all his brethren he dwelt (נָפָל).””
Source
1167
A.D.
Ibn Ezra Jewish
1089–1167
גור יגור. According to R. Jonah: they will surely gather together; comp. ממגורות barns, (Joel 1:17). The meaning of the whole verse is accordingly: Is it possible, that any alliance should be made except with my permission ? (The alliance between Gog and Magog is here referred to.) He who is now thy ally, and will then become thy enemy, will fall. I take גור יגור in its usual meaning and explain the verse thus: Can there dwell any stranger with thee in my land, except it be with my will; he who desires to dwell with thee in my land, עליך יפול must surrender to thee. The verb נפל has here the same meaning as in אל הכשדים אתה נופל thou fallest away to the Chaldӕans (Jer. 37:13); and in על פני כל אחיו נפל he surrendered to all his brethren (Gen. 25:18); namely: to submit to the authority of.”
Source
1256
A.D.
Thomas Aquinas Catholic
1225–1274
“Sing, O barren one. Here, against the casting down of things, he promises the remedy of exaltation: and first he promises a multitude against a paucity; second, the restoration of honor against confusion, do not fear; third, prosperity against former adversity, poor little one. Concerning the first he does three things. First he foretells the multitude of children, indicating the praise of thanksgiving: "O barren one" — Jerusalem, who do not bear; "because forsaken" — deserted; "sing" — to God, for the benefits granted. The gladness of those who praise: "sing forth praise" — for a song is the exultation of the mind broken forth into voice; and the greatness of the gladness: "neigh" — in the manner of a horse, unable because of the greatness to form a voice to express it. Jer. 31: Exult in gladness, Jacob. Ps. 146: Let praise of our God be pleasant and comely. And promising the multitude of children: "because many" — as if to say, your children will be multiplied more, although you are deserted, than that of the cities which have husbands for begetting. 1 Reg. 2: until the barren woman has borne very many, and she who had many children is weakened. Second he exhorts to the enlargement of the place, under the metaphor of a tent: "enlarge the place" — as to the ground on which it is extended; "the skins" — by which it is covered; "the cords" — by which the pegs are bound; "the nails" — by which the boards are joined, or the pegs themselves. And these are read to have been in the tabernacle of the covenant: Exod. 26, and 36. On account of this multitude of men it is fitting to seek a greater dwelling than the land of promise is. Above, 49: still the children of barrenness say, etc. Third he foretells the fulfillment of the exhortation: "for to the right hand" — as if to say, you shall spread yourself on every side: which was fulfilled in the time of the Maccabees, when certain cities from the region of Samaria, and from others, were added to the kingdom of the Jews. Gen. 24: may your seed possess the gates of your enemies. Do not fear. Here he promises the restoration of former honor, against the confusion which they had previously endured. Second, the firmness of the promise: as in the days of Noah. Concerning the first he does two things. First he promises the forgetting of the former confusion: "you shall not be confounded" — inwardly; "you shall not blush" — outwardly. "You shall be ashamed" — from the consideration of your baseness; "you shall forget" — because of the abundance of glory; "of youth" — when you sinned in the desert; "of widowhood" — when you were separated from God in the captivity of Babylon. Above, 45: you shall not be confounded, nor shall you blush. Sopho. 3: in that day you shall not be confounded for all your devisings. Second he promises the restoration of former honor: and first he sets down the restoration as to dominion, "because he shall rule"; above, 26: O Lord, they have possessed us; and as to marriage, "a forsaken wife." Jerem. 3: if a man put away his wife, and she depart from him and marry another man, shall she return to him any more? Second he promises the enlargement of honor as to the multitude of honors: "says the Lord" — "in a little" — you have suffered little in respect of the things which I, having mercy, shall bestow on you. 2 Corinth. 4: for that which is at present is momentary. And as to duration, "in a moment" — as if to say: for a brief time you have felt my anger, in respect of that in which I will have mercy on you. Above, 26: hide yourself a little while. But all these things that have been said are expounded mystically of the calling of the Gentiles: because the Gentile world, barren at first, afterward gathered many children, according to the Gloss. As in the days. Here he shows the firmness of the promise. And first from the likeness of the former promise: "I have sworn" — I have firmly determined, provided, however, that you remain in my precepts. Gen. 9: I will establish my covenant with you, and with your seed after you. Eccli. 44: the covenants of the age. Second, from the working of stable creatures: "for the mountains" — as if to say: it is easier for mountains and hills to be changed than for my words to be made void. Or by mountains and hills, the powerful of the world. Ps. 45: we will not fear, while the earth is troubled. Note on that word, "sing, O barren one," that there is a barrenness, first, of perverse action. Job 15: the congregation of the hypocrite is barren. Second, of sacred contemplation. Genes. 29: Rachel was barren. Third, of temporal tribulation. Above, 49: the children of barrenness shall still say in your ears. Likewise note, on that phrase "enlarge the tent," that the heart must be enlarged, first, on account of the greatness of the guest. Jerem. 23: do not I fill heaven and earth, says the Lord? Second, on account of the multitude of gifts. Below, 60: you shall see, and abound, and your heart shall be enlarged. Third, on account of the fulfilling of the way. Psalm. 118: I have run the way of your commandments. Likewise on that phrase "in great mercies," that the mercies to come are great: first because they are intrinsic. Rom. 8: I reckon that the sufferings of this time are not worthy to be compared to the glory to come that shall be revealed in us. Second, because they are eternal. 2 Cor. 4: for the things which are seen are temporal; but the things which are not seen are eternal. Third, because they are perfect. Luc. 1: for behold, from now on all generations shall call me blessed. Fourth, because they are extended to many. Luc. 14: a certain man made a great supper, and invited many. Fifth, because they are whole. Apoc. 21: God shall wipe away every tear from the eyes of the saints. Poor little one. Here he promises prosperity against adversity: and first he recalls the former adversity: "poor little one" — Jerusalem despoiled of goods; "by tempest" — by adversity. Above, 18: to a nation rent and torn I will send you. Second he promises future prosperity, both as to the abundance of goods, setting forth a metaphor: "behold I will lay" — as it were in a pavement, by the "stones," "precious," signifying men eminent in virtues, "in order," each one in his own order: Tob. 13: the gates of Jerusalem; and explaining it as to the doctrine of divine knowledge: "all" — Jer. 31: I will give my law in their bowels, and write it in their heart. As to the abundance of peace: "multitude." Psalm. 118: much peace have they that love your law. And as to the justice of works: "and in justice." Above, 1: Sion shall be redeemed in judgment; and they shall bring her back in justice. Second, as to the freedom from evils, promising first the escape from dangers: "depart" — that is, you shall depart, because you shall not suffer calumny. Ps. 71: he shall humble the slanderers. Second, the adherence of strangers: "behold, the sojourner" — because many from among the Gentiles going forth from captivity adhered. Below, 56: let not the son of the stranger, who adheres to the Lord, say: the Lord will divide me by separation from his people. Third, promising the destruction of enemies: "behold I." And first he shows the power of the one promising, setting forth a comparison: "the smith" — the persecutor, who blows upon the vessels in the fire of tribulation, adversaries, according to his own will: Job 41: his breath, coals; and explaining it: "I have created." 1 Reg. 2: the Lord kills and makes alive. Second he sets forth the promise: "every vessel" — that is, he will scatter every thing formed, as to those who assail by deeds; and "every tongue," as to those who assail by words. Above, 41: and they shall be as if they were not.”

Post-Reformation

c. 1650 – 1900
1849
A.D.
1774–1849
“To thee, in the inheritance. This was verified in the Church. We have no accout of many being converted before.”
1871
A.D.
1871
“gather together, &c.--that is, If it should happen that enemies "gather together" against thee (Psa 2:2), they will not have been sent by Me (compare Hos 8:4) as instruments of My wrath (nay, it will be with My disapproval); for "whosoever shall gather together," &c. (Psa 59:3). fall for thy sake--rather, "shall come over to thy side" [LOWTH]. Literally, "fall to thee" (Jer 21:9; Jer 39:9). To be fully fulfilled to Jerusalem hereafter (Zac 14:16).”
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.