Deutéronome 32:39

When the Word of the Lord shall reveal Himself to redeem His people, He will say to all the nations: Behold now, that I am He who Am, and Was, and Will Be, and there is no other God beside Me: I, in My Word, kill and make alive; I smite the people of the Beth Israel, and I will heal them at the end of the days; and there will be none who can deliver them from My hand, Gog and his armies whom I have permitted to make war against them.

I, I Either a mere stylistic repetition, as in “I, I” [Isaiah 51: 12], or, more correctly, “I am I”, meaning, I am the same One — I have not changed. There is no other actor working with Him — I am the One Who has brought death to Israel, and I am also the One Who shall bring life to them. And just as they did not escape from Me, so, too, there will be none to save you from My hand — i.e., you, too, are in My hands, until I shall have done you justice. Many say [Pesaḥim 68a] that this is the verse from which we learn the doctrine of the resurrection of the dead, since the verse first says I slay, and then says I bring life (as in “God kills and gives life” [I Samuel 2: 6], as evidenced by the subsequent statement that God “lowers to the grave, and raises up” [I Samuel 2: 6]). Others [Breshit Rabba on Genesis 9: 5] have said that the doctrine is derived from the verse “Surely your blood of your souls” [Genesis 9: 5] [because the prohibition of suicide that is derived from the verse would be meaningless without an afterlife — Translator], or from “It will be our privilege” [6: 25] or [Qiddushin 40a] from “For He is your life” — in this world — “and your longevity” — in the World to Come [30: 20], or [Qiddushin 39b] from “that it may be well with you” [5: 16] [see also Sanhedrin 90b — Translator]. Hai Gaon, of blessed memory, has said that Scripture did not need to explain the doctrine of the World to Come, because it has been transmitted to us through tradition. My opinion is that the Torah was given to everyone, not to the lone individual, and that not one man in a thousand can comprehend the doctrine of the World to Come, on account of its profundity. To understand the reward of the World to Come requires an understanding of the nature of the soul. It comes about in return for one’s “service of the heart”, the service of which is to contemplate the works of God , for they are the ladder by means of which one ascends to the level of knowledge of God , the ultimate goal. Moreover, the Torah has provided, for the discerning, the illustration of the “Tree of Life” [cf. comment on Genesis 3: 24], through which the Cherubim [Genesis 3: 24] receive the power of immortality. Whoever eats of the Tree of Life will live forever, like the ministering angels [cf. Genesis 3: 22]. Similarly, in the forty-ninth Psalm, there is the mysterious passage, “But God will redeem my soul from the power of the grave, for He will take me” [Psalms 49: 16], and also, “afterward, You will take me into honor” [Psalms 73: 24]. Both passages employ the verb “to take”, just as is used to describe Ḥanokh [Genesis 5: 24] and Elijah [II Kings 2: 10]. The discerning will understand how the Psalmist can say “their soul’s redemption is too costly” [Psalms 49: 9] and then say later “He will redeem my soul” [Psalms 49: 16].

ראו עתה כי אני אני הוא, G’d addresses the nations of the earth who have said: ”where is their G’d?,” that when they would now experience G’d’s judgment and how He avenges the injustice done to His people, that He is very much around, notwithstanding their mockery of Him.

ראו עתה כי אני אני הוא, realise now that it had been I Who had brought disaster in exile upon you!

ואין אלוהים עמדי, I had not required the assistance of any other deity. Your misfortune was not due to any celestial forces appointed by Me.

אני אמית ואחיה, only I decree death and resurrection.(compare Ezekiel 37,12)

מחצתי, I have smashed, by decreeing your unsettled condition, forcing you to move from one country to another without taking permanent root in any of them. (compare Kings I 14,15) where the prophet compares the existence of the Jewish people after G’d has chastised them as similar to that of a reed which is constantly moving.

ואני ארפא, and only I can bring healing, as described in Isaiah 30,26.

ראו עתה כי אני אני הוא, “See, now, that I, I am He;” As to those who had mockingly asked where the Israelites’ G–d was when they were in exile and persecuted, now they would see that He is not only the G–d of the Israelites but the G–d over the whole universe and what it contains. He is about to demonstrate this. And as far as considering themselves as His junior partners,

ואין אלהים עמדי, “there is no other deity beside Me.”
אני אתית ואני אחיה, “I cause death, and I resurrect (exclusively).” I alone possess this power, and only I am able to resurrect the dead.

מחצתי ואני ארפא, “I have wounded and I am able to heal.” I will heal them, (My people). Concerning what you gentiles have said sarcastically: יקומו ויעזרכם, “let them arise and help you,” there is no one who can help other than I who can help you. By the same token, no one can save you from Me. (if I decide your destruction).