For the Lord shall judge by fire, and by his sword unto all flesh, and the slain of the Lord shall be many.

“For with fire of Gehinnom will the Lord contend with His adversaries, and since He is the plaintiff and the judge, the expression of contending is appropriate for Him, for He, too, presents His claim to find their iniquity and their transgression. Comp. (Ezekiel 38:22) “And I will contend with him (וְנִשְׁפַּטְתִּי)”; (Jer. 2:35) “Behold, I contend with you.” It is an expression of debate. Derajjsner in O.F. [And its simple meaning is: For with the fire of the Lord and with His sword, all flesh shall be judged. Similarly, there are many inverted verses in Scriptures.]”

“Thus says the Lord. Here he determines the manner of the execution of the sentence already given: and first specifically as regards the Jews; second universally as regards all: but I, their works and thoughts. The first is divided into two: in the first he excludes false confidence; second he sets forth and determines the sentence given, as to the manner of its execution: Hear the word of the Lord. Concerning the first there are two parts. First he excludes false confidence in the holiness of the temple, showing that the temple is not the place of God: both from the greatness of God, who fills all things — whose seat heaven is called, because it shares abundantly in his goodness, just as a seat holds the greater part of the one sitting; while earth is his footstool, because the earth shares least in his goodness, just as the outermost part reaches only to the footstool — or by heaven the saints are meant, and by earth the earthly-minded. 3 Kings 8: if heaven and the heaven of heavens do not contain you. Jeremiah 23: I fill heaven and earth. Acts 17: not in the hand-made things of the temple. Then from rest: because each thing rests in the place that is its own place; but God does not rest in anything, rather all things rest in him, as made by him. And what is his place? Above, ch. 40: lift up on high. And he gives a useful remedy: but to whom — the poor one, that is, the humble man who considers himself small as to the present; the contrite, as to past sins; the trembling, as to his resolve concerning what is to be done in the future. Ecclesiasticus 15: his eyes are upon those who fear him. Second, he excludes the confidence they had conceived from the rite of sacrifices: and first he sets down their reprobation: he who sacrifices an ox — as if he were to say: their sacrifices are so abominable, as if they were doing something against the law, because they were offering the same things to idols. He who blesses — that is, praises and venerates. Above, ch. 1: do not offer sacrifice any more. Second, he shows the reason for the reprobation, first setting down their fault: they have chosen all these things — namely, the sacrifices — walking in their own ways, evil ones. Proverbs 2: they rejoice when they have done evil, and exult in the worst of things. Second, he threatens punishment: hence, and I — Proverbs 3: he himself will mock the mockers. Job 3: the fear that I feared has come upon me, and what I dreaded has happened to me. Third, he charges the sinners with hardness of heart: because I called — Proverbs 1: I called, and you refused. Hear the word of the Lord. Here he carries out the manner of executing the sentence already given: and first as to the rewards of the good; second as to the punishments of the wicked: and it shall be known. The first is in two parts. First he rouses attention: you who tremble, out of reverence for his words. Ecclesiasticus 2: you who fear the Lord, believe in him. Second, he pursues the promise: and first as to vengeance upon the mockers, setting down their mockery: your brothers have said. Let him be glorified — as if to say: let the glory of the Lord appear, which you expect — as if to say: it will never appear. Above, ch. 5: he will come quickly and swiftly, he will not fail nor grow weary in it. And foretelling their confusion: but they shall be confounded, in this way: a voice of the people, fearing; a voice of the Lord, as to the tumult of enemies. Zephaniah 1: the voice of the day of the Lord is bitter. Second, he carries out the promise as to the abundance of good things: and first as to the reuniting of the people, setting down the promise: before she was in labor — that is, suddenly, and at once, the children of Jerusalem shall be gathered to her, just as if a woman should suddenly bring forth a son, with no labor going before. Above, ch. 37: the children have come as far as the birth. Mystically it is expounded of the childbearing of the Blessed Virgin, and of the childbearing of the Church in the conversion of the faithful, and of the bringing-forth of the eternal generation. And he introduces a question of wonder: who has ever heard such things? Above, ch. 49: who has begotten for me? And he sets down the answer in the person of the Lord: shall not I myself bring forth? — gathering the Jews, or converting the faithful, or the Son from eternity. Similarly, Psalm 93: he who planted the ear, shall he not hear? Or he who formed the eye, does he not consider? And these arguments hold, if that which is of perfection in creatures is attributed to him, with everything that belongs to imperfection removed. Second, he promises immense consolation to those gathered. And first he invites others to rejoice with them: rejoice with Jerusalem — in her, as in the object of joy — setting down the condition of those who rejoice together, as to affection: you who love. Canticle of Canticles 5: eat, O friends, and drink, and be inebriated, dearest ones. As to the sign of affection: you who mourn. Matthew 5: blessed are they who mourn, for they shall be comforted. And the fruit of that shared rejoicing, as to the sharing of gladness, or of peace: that you may suck — Canticle of Canticles 1: your breasts are better than wine. As to the sharing of glory: that you may milk it out, as those who milk out milk. Job 22: then you shall abound in delights over the Almighty. Second, he promises a copious bestowal of peace: for thus says the Lord: I will turn — so that it may be called an overflow, like a river which, though it comes down with great force, does not overflow. And of glory, and as it were a torrent. Above, ch. 48: it would have been made like a river. Third, he promises the full reception of consolation. First as to the administering of the nations: which you shall suck — unto the glory of the nations, because the kings of the nations themselves shall comfort you, and shall sustain you. Hence there follows, at the breasts. Mystically he speaks of the apostles, who rejoiced in the glory of the nations swiftly converted, and carried them, as it were, to the breasts by gentle admonitions. Above, ch. 60: you shall suck milk. Second, as to the divine protection: as if to someone, a mother. Hebrews 12: you have forgotten the consolation. Third, as to the enjoyment of good things: you shall see — the good things given you by God; your bones — you who in adversity were like dry bones. Ezekiel 37: dry bones, hear the word of the Lord. Or, you shall see the divine essence. Ecclesiastes 11: light is sweet, and it is delightful for the eyes to see the sun. Bones, unto the resurrection. And it shall be known. Here he promises punishments to the wicked: and first he threatens punishment, setting down the indignation of the judge: the hand, afflicting the wicked among his servants. Or, the hand of consolation, among his servants, through its effect. Above, ch. 27: there is no indignation in me. He also sets down the greatness of the punishment: for behold, the Lord — in fire, by which the city was to be burned, or by which the world was to be purged. Chariots — the army of the Chaldeans, in which God comes, as it were; or the Angels who will come with him to judgment. Psalm 96: fire shall go before him. Amos 9: they shall perish by the sword of God. He also sets down the multitude of those punished: they shall be multiplied. Above, ch. 34: for the victim of the Lord is in Bosra, and a great slaughter in the land of Edom. Second, he reproaches their guilt: who were sanctifying themselves, thinking to cleanse themselves from uncleanness by waters, or even by the sacrifices of idols, in the gardens, in which they worshipped idols, or gave themselves over to pleasure, after one, coupling with women after the manner of beasts. Or, behind the door — literally, the mouse, the dormouse, against the law, Leviticus 11. Above, ch. 65: they eat swine's flesh, and unclean broth. But I. Here he pursues the manner of the discernment as regards all in common: and first he proclaims the universal judgment: their works and thoughts — judging, as it were, for both together; I come, on the day of judgment. Or, the various kingdoms of your enemies, and destroying the wicked among you. They shall come, to Jerusalem after your return, or to judgment, or to the faith. Joel 3: behold, I will raise them up out of the place in which you sold them. Second, he sets down the summons: and I will set among them — that is, among the Jews who shall be with Zerubbabel and the other leaders — a sign, the edict of Cyrus, to the nations, to which the Jews had been scattered; to Lydia, those who hold the arrow, because they are good archers; my glory, which shall appear in your deliverance. Above, ch. 11: he shall lift up a sign among the nations. Or, he sets the sign of the cross among the apostles, that all may be turned to God, as it were preparing them for judgment. Third, he sets down the preparation of those who are to be judged: and first as to the good; second as to the wicked: and they shall go forth, and shall see. The first is in two parts. First, as to the Jews, setting down their honorable return: they shall bring them on horses — by which are signified the aids which those returning had from the Gentiles. Baruch 5: the Lord shall bring these to you. Or there are signified the various conditions of those who are converted to the faith, as the Gloss expounds. Second, the exaltation of their return, first as to dignity: and I will take — which was fulfilled literally in the Jews, and also in the apostles. Above, ch. 61: you shall be called the priests of the Lord; it shall be said of you, ministers of our God. Second, as to the preservation of their offspring: for as the new heavens, as above, ch. 65 — so shall it stand, forever. Jeremiah 31: if these laws shall fail before me, says the Lord, then the seed of Israel also shall fail. Or, the saints shall stand forever, renewed like heaven and earth. Third, as to the duration of their glory: and it shall be month — as though month shall succeed month, and feast shall succeed feast, in your prosperity. Above, ch. 29: year has been added to year, and the solemnities have run their course. Mystically, the Church after the end; spiritual rest after carnal. Second, as to the Gentiles: and all shall come — because from the various nations they came to Jerusalem to worship the Lord. Psalm 85: all the nations shall come and shall adore before you, O Lord. Or, on the day of judgment: and they shall go forth. Here he sets down the second judgment, as regards the wicked: and first the outflow of the punishment: and they shall go forth, coming to Jerusalem, and they shall see, in the ancient tombs, and in the fields, the bones of their dead fathers. Above, ch. 34: their slain shall be cast out, and from their carcasses a stench shall rise. Or, the saints shall see the damned falling into damnation. Second, he sets down the duration of the punishment: their worm — of conscience, by which even the dead shall be tormented; and fire — of hell. Judith 16: he will give fire and worms into their flesh. Third, the delight taken in these punishments, as regards those who see them: and they shall be unto satiety to all flesh — that is, to the saints. Psalm 57: the just shall rejoice when he shall see the revenge. From these punishments may he free us, who has granted both to begin and to complete. And thus ends the sentence and the literal exposition on Isaiah according to Brother Thomas Aquinas, which Brother Iacobinus of Asti, of the province of Lombardy, at that time a student in the general house of studies at Naples, transcribed into legible letters, completing the authorities. He also arranged collations at certain places upon each of the lectures, and this he did for the benefit of the friars of our order, and that copies of the said writings might be had. Therefore, praise be to him who granted both to begin and to complete. Amen.”

“Rather, "With fire will Jehovah judge, and with His sword (He will judge) all flesh." The parallelism and collocation of the Hebrew words favor this (Isa 65:12). all flesh--that is, all who are the objects of His wrath. The godly shall be hidden by the Lord in a place of safety away from the scene of judgment (Isa 26:20-21; Psa 31:20; Th1 4:16-17).”

“Jehovah appears with these warlike terrors because He is coming for a great judgment. "For in the midst of fire Jehovah holds judgment, and in the midst of His sword with all flesh; and great will be the multitude of those pierced through by Jehovah." The fire, which is here introduced as the medium of judgment, points to destructive occurrences of nature, and the sword to destructive occurrences of history. At the same time all the emphasis is laid here, as in Isa 34:5-6 (cf., Isa 27:1), upon the direct action of Jehovah Himself. The parallelism in Isa 66:16 is progressive. Nishpat 'ēth, "to go into judgment with a person," as in Eze 38:22 (cf., עם in Isa 3:14, Joe 3:2; Ch2 22:8; μετά, Luk 11:31-32). We find a resemblance to Isa 66:16 in Zep 2:12, and this is not the only resemblance to our prophecy in that strongly reproductive prophet.”