The interpretation timeline
Deuteronomy 32:39 Douay-Rheims

See ye that I alone am, and there is no other God besides me: I will kill and I will make to live: I will strike, and I will heal, and there is none that can deliver out of my hand.

A.D. 346 – 1771 8 witnesses 10 excerpts

Patristic

before A.D. 750
346
A.D.
c. A.D. 270–346
“We are sure that he causes to die. We see it. Just so also is it sure and worthy of belief that he makes alive. And from all that I have explained to you, receive and believe that in the day of the resurrection your body shall arise in its entirety, and you shall receive from our Lord the reward of your faith. And in all that you have believed, you shall rejoice and be made glad.”
Source
367
A.D.
Hilary of Poitiers Patristic
c. A.D. 310–367
“In order that the godlessness of the heretics may not perhaps apply the meaning of these words to the unbegotten God the Father, the sense itself of the words and the authority of the apostle come to our aid. He, as we have already explained, interprets this whole passage as pertaining to the person of the only-begotten God.”
Source
379
A.D.
Basil of Caesarea Patristic
c. A.D. 330–379
“He himself permits the suffering which he again restores. The One who strikes is the One who heals. The afflictions precede in order that the graces may be lasting. Only then do we exert ourselves exceedingly for the preservation of what has been given.”
395
A.D.
Gregory of Nyssa Patristic
c. A.D. 335–395
“It is not possible for the good to exist in me unless it is made to live through the death of my enemy. As long as we keep grasping opposites with each of our hands, it is impossible for there to be participation in both elements in the same being. For if we are holding evil, we lose the power to take hold of virtue.”
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“He is God, so he also takes pity. He gets angry, and he takes pity. He gets angry and strikes; he takes pity and heals. He gets angry and does to death; he takes pity and brings to life. In one person he does this. It's not that he does some people to death and brings others to life, but in the same people he is both angry and gentle. He is angry with errors; he is gentle with bad habits put right. "I will strike and I will heal: I will kill and I will make alive." One and the same Saul, afterward Paul, he both laid low and raised up. He laid low an unbeliever; he raised up a believer. He laid low a persecutor; he raised up a preacher.”
Source
“[Paul's conversion] fulfilled in him what was written in the prophet, "I will strike, and I will heal." What God strikes, you see, is that in people which lifts up itself against God. The surgeon isn't being heartless when he lances the tumor, when he cuts or burns out the suppurating sore. He's causing pain; he certainly is, but in order to restore health. It's a horrid business; but if it wasn't, it wouldn't be any use.”
Source
“So the apostle was petrified, knocked down and laid low, raised up and patched up. The words, you see, were realized in him: "It is I that will strike and I that will heal." You see, it doesn't say, "I will heal, and I will strike," but "I will strike, and I will heal." I will strike you and give myself to you. Thus being laid low, he was horrified at his own justice, in which he was certainly without reproach, praiseworthy, great, even glorious among the Jews. He reckoned it was waste, he thought it was loss, he counted it dung, "that he might be found in him, not having his own justice, which is from the law; but that which is through the faith of Christ, which is," he says, "from God."”
Source

Scholastic

c. 1100 – 1500
1105
A.D.
Rashi Jewish
1040–1105
ראו עתה SEE NOW — Realise now from the punishment which I have brought upon you and from which there was no one to save you, and, on the other hand, from the help which I will render you and there will be none who can prevent Me, אני אני הוא [THAT] IT IS I, EVEN I — I am He Who have the power to abase (make low) and it is I who have the power to raise, ואין אלהים עמדי AND THERE IS NO GOD WITH ME — i.e. standing against Me to prevent this. עמדי means, who is my equal and like Me. ואין מידי מציל AND THERE IS NONE WHO CAN DELIVER OUT OF MY HAND those who rebel against Me.”
Source

Post-Reformation

c. 1650 – 1900
1714
A.D.
Matthew Henry Reformed
1662–1714
“This conclusion of the song speaks three things: I. Glory to God, Deu 32:39. "See now upon the whole matter, that I, even I, am he. Learn this from the destruction of idolaters, and the inability of their idols to help them." The great God here demands the glory, 1. Of a self-existence: I, even I, am he. Thus Moses concludes with that name of God by which he was first made to know him (Exo 3:14), "I am that I am. I am he that I have been, that I will be, that I have promised to be, that I have threatened to be; all shall find me true to my word." The Targum of Uzzielides paraphrases it thus: When the Word of the Lord shall reveal himself to redeem his people, he shall say to all people, See that I now am what I am, and have been, and I am what I will be, which we know very well how to apply to him who said to John, I am he who is, and was, and is to come, Rev 1:8. These words, I even I, am he, we meet with often in those chapters of Isaiah where God is encouraging his people to hope for their deliverance out of Babylon, Isa 41:4; Isa 43:11, Isa 43:13, Isa 43:25, Isa 46:4. 2. Of a sole supremacy. "There is no god with me. None to help with me, none to cope with me." See Isa 43:10, Isa 43:11. 3. Of an absolute sovereignty, a universal agency: I kill, and I make alive; that is, all evil and all good come from his hand to providence; he forms both the light of life and the darkness of death, Isa 45:7; Lam 3:37, Lam 3:38. Or, He kills and wounds his enemies, but heals and makes alive his own people, kills and wounds with his judgments those that revolt from him and rebel against him; but, when they return and repent, he heals them, and makes them alive with his mercy and grace. Or it denotes his incontestable authority to dispose of all his creatures, and the beings he has given them, so as to serve his own purposes by them: Whom he will he slays, and whom he will he keeps alive, when his judgments are abroad. Or thus, Though he kill, yet he makes alive again: though he cause grief, yet will he have compassion, Lam 3:32. Though he have torn, he will heal us, Hos 6:1, Hos 6:2. The Jerusalem Targum reads it, I kill those that are alive in this world, and make those alive in the other world that are dead. And some of the Jewish doctors themselves have observed that death, and a life after it, that is, eternal life, is intimated in these words. 4. Of an irresistible power, which cannot be controlled: Neither is there any that can deliver out of my hand those that I have marked for destruction. As no exception can be made against the sentence of God's justice, so no escape can be made from the executions of his power. II. Terror to his enemies, Deu 32:40-42. Terror indeed to those that hate him, as all those do that serve other gods, that persist in wilful disobedience to the divine law, and that malign and persecute his faithful servants. These are those to whom God will render vengeance, those his enemies that will not have him to reign over them. In order to alarm such in time to repent and return to their allegiance, the wrath of God is here revealed from heaven against them. 1. The divine sentence is ratified with an oath (Deu 32:40): He lifts up his hand to heaven, the habitation of his holiness; this was an ancient and very significant sign used in swearing, Gen 14:22. And, since he could swear by no greater, he swears by himself and his own life. Those are miserable without remedy that have the word and oath of God against them. The Lord hath sworn, and will not repent, that the sin of sinners shall be their ruin if they go on in it. 2. Preparation is made for the execution: The glittering sword is whet. See Psa 7:12. It is a sword bathed in heaven, Isa 34:5. While the sword is in whetting, space is given to the sinner to repent and make his peace, which, if he neglects, will render the wound the deeper. And, as the sword is whet, so the hand that is to wield it takes hold on judgment with a resolution to go through with it. 3. The execution itself will be very terrible: The sword shall devour flesh in abundance, and the arrows be made drunk with blood, such vast quantities of it shall be shed, the blood of the slain in battle, and of the captives, to whom no quarter shall be given, but who shall be put under military execution. When he begins revenge he will make an end; for in this also his work is perfect. The critics are much perplexed with the last clause, From the beginning of revenges upon the enemy. The learned bishop Patrick (that great master) thinks it may admit this reading, From the king to the slave of the enemies, Jer 50:35-37. When the sword of God's wrath is drawn it will make bloody work, blood to the horse-bridles, Rev 14:20. III. Comfort to his own people (Deu 32:43): Rejoice, O you nations, with his people. He concludes the song with words of joy; for in God's Israel there is a remnant whose end will be peace. God's people will rejoice at last, will rejoice everlastingly. Three things are here mentioned as the matter of joy: - 1. The enlarging of the church's bounds. The apostle applies the first words of this verse to the conversion of the Gentiles. Rom 15:10, Rejoice you Gentiles with his people. See what the grace of God does in the conversion of souls, it brings them to rejoice with the people of God; for true religion brings us acquainted with true joy, so great a mistake are those under that think it tends to make men melancholy. 2. The avenging of the church's controversies upon her adversaries. He will make inquisition for the blood of his servants, and it shall appear how precious it is to him; for those that spilt it shall have blood given them to drink. 3. The mercy God has in store for his church, and for all that belong to it: He will be merciful to his land, and to his people, that is, to all every where that fear and serve him. Whatever judgments are brought upon sinners, it shall go well with the people of God; in this let Jews and Gentiles rejoice together.”
Source
1771
A.D.
John Gill Reformed
1697–1771
“For I lift up my hand to heaven,.... Which is a gesture used in swearing, Gen 14:22, and is ascribed to a divine Person, Eze 20:5; and particularly to Christ the angel, that is so wonderfully described, Rev 10:1; though sometimes it is used, as Aben Ezra observes, to excite the attention of hearers, but here it signifies swearing; and so the Targums of Jonathan and Jerusalem paraphrase it,"I have lift up my hands with an oath to heaven;''and to the same sense is the Septuagint version: and say, I live for ever; which is the form of an oath; when men swear, they are to swear, the Lord liveth, or to swear by the living God, and him only, Jer 4:2; and when the Lord swears in this manner, he swears by his life, by himself, because he can swear by no greater; and his form of swearing is, "as truly as I live, saith the Lord", Num 14:21; so the above angel is said to swear by him that liveth for ever and ever, Rev 10:6; and since Christ is the living God, without beginning of days, and end of life, and lives for evermore, he may be thought to swear by himself, by his own life, which is for ever; and as the oath of the Lord is used in condescension by him, to confirm the faith of his people in the immutability of his counsel and promises, and to ascertain unto them the sure performance of them; so it is also used to assure wicked men of the certain performance of his threatenings; and it is as if Christ here said, as sure as I am the living God, and do and shall live for ever, I will most certainly do the things which next follow.”
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.