A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
isa 63:1MESSIAH COMING AS THE AVENGER, IN ANSWER TO HIS PEOPLE'S PRAYERS. (Isa. 63:1-19)
Who--the question of the prophet in prophetic vision.
dyed--scarlet with blood (Isa 63:2-3; Rev 19:13).
Bozrah--(See on Isa 34:6).
travelling--rather, stately; literally, "throwing back the head" [GESENIUS].
speak in righteousness--answer of Messiah. I, who have in faithfulness given a promise of deliverance, am now about to fulfil it. Rather, speak of righteousness (Isa 45:19; Isa 46:13); salvation being meant as the result of His "righteousness" [MAURER].
save--The same Messiah that destroys the unbeliever saves the believer.
isa 63:2The prophet asks why His garments are "dyed" and "red."
winefat--rather, the "wine-press," wherein the grapes were trodden with the feet; the juice would stain the garment of him who trod them (Rev 14:19-20; Rev 19:15). The image was appropriate, as the country round Bozrah abounded in grapes. This final blow inflicted by Messiah and His armies (Rev 19:13-15) shall decide His claim to the kingdoms u surped by Satan, and by the "beast," to whom Satan delegates his power. It will be a day of judgment to the hostile Gentiles, as His first coming was a day of judgment to the unbelieving Jews.
isa 63:3Reply of Messiah. For the image, see Lam 1:15. He "treads the wine-press" here not as a sufferer, but as an inflicter of vengeance.
will tread . . . shall be . . . will stain--rather preterites, "I trod . . . trampled . . . was sprinkled . . . I stained."
blood--literally, "spirited juice" of the grape, pressed out by treading [GESENIUS].
isa 63:4is--rather, "was." This assigns the reason why He has thus destroyed the foe (Zep 3:8).
my redeemed--My people to be redeemed.
day . . . year--here, as in Isa 34:8; Isa 61:2, the time of "vengeance" is described as a "day"; that of grace and of "recompense" to the "redeemed," as a "year."
isa 63:5The same words as in Isa 59:16, except that there it is His "righteousness," here it is His "fury," which is said to have upheld Him.
isa 63:6Rather, preterites, "I trod down . . . made them drunk." The same image occurs Isa 51:17, Isa 51:21-23; Psa 75:8; Jer 25:26-27.
will bring down . . . strength to . . . earth--rather, "I spilled their life-blood (the same Hebrew words as in Isa 63:3) on the earth" [LOWTH and Septuagint].
isa 63:7Israel's penitential confession and prayer for restoration (Psa 102:17, Psa 102:20), extending from Isa. 63:7-64:12.
loving-kindnesses . . . praises . . . mercies . . . loving-kindnesses--The plurals and the repetitions imply that language is inadequate to express the full extent of God's goodness.
us--the dispersed Jews at the time just preceding their final restoration.
house of Israel--of all ages; God was good not merely to the Jews now dispersed, but to Israel in every age of its history.
isa 63:8he--Jehovah "said," that is, thought, in choosing them as His covenant-people; so "said" (Psa 95:10). Not that God was ignorant that the Jews would not keep faith with Him; but God is here said, according to human modes of thought to say within Himself what He might naturally have expected, as the result of His goodness to the Jews; thus the enormity of their unnatural perversity is the more vividly set forth.
lie--prove false to Me (compare Psa 44:17).
so--in virtue of His having chosen them, He became their Saviour. So the "therefore" (Jer 31:33). His eternal choice is the ground of His actually saving men (Eph 1:3-4).
isa 63:9he was afflicted--English Version reads the Hebrew as the Keri (Margin), does, "There was affliction to Him." But the Chetib (text) reads, "There was no affliction" (the change in Hebrew being only of one letter); that is, "In all their affliction there was no (utterly overwhelming) affliction" [GESENIUS]; or, for "Hardly had an affliction befallen them, when the angel of His presence saved them" [MAURER]; or, as best suits the parallelism, "In all their straits there was no straitness in His goodness to them" [HOUBIGANT], (Jdg 10:16; Mic 2:7; Co2 6:12).
angel of his presence--literally, "of His face," that is, who stands before Him continually; Messiah (Exo 14:19; Exo 23:20-21; Pro 8:30), language applicable to no creature (Exo 32:34; Exo 33:2, Exo 33:14; Num 20:16; Mal 3:1).
bare them-- (Isa 46:3-4; Isa 40:11; Exo 19:4; Deu 32:11-12).
isa 63:10vexed--grieved (Psa 78:40; Psa 95:10; Act 7:51; Eph 4:30; Heb 3:10, Heb 3:17).
he fought--rather, "He it was that fought," namely, the angel of His presence [HORSLEY], (Lam 2:5).
isa 63:11remembered--Notwithstanding their perversity, He forgot not His covenant of old; therefore He did not wholly forsake them (Lev 26:40-42, Lev 26:44-45; Psa 106:45-46); the Jews make this their plea with God, that He should not now forsake them.
saying--God is represented, in human language, mentally speaking of Himself and His former acts of love to Israel, as His ground for pitying them notwithstanding their rebellion.
shepherd--Moses; or if the Hebrew be read plural, "shepherds," Moses, Aaron, and the other leaders (so Psa 77:20).
put . . . Spirit . . . within him--Hebrew, "in the inward parts of him," that is, Moses; or it refers to the flock, "in the midst of his people" (Num 11:17, Num 11:25; Neh 9:20; Hag 2:5).
isa 63:12The right hand of Moses was but the instrument; the arm of God was the real mover (Exo 15:6; Exo 14:21).
dividing the water-- (Neh 9:11; Psa 78:13).
isa 63:13deep--literally, "the tossing and roaring sea."
wilderness--rather, the "open plain" [HORSLEY], wherein there is no obstacle to cause a horse in its course the danger of stumbling.
isa 63:14As a beast . . . rest--image from a herd led "down" from the hills to a fertile and well-watered "valley" (Psa 23:2); so God's Spirit "caused Israel to rest" in the promised land after their weary wanderings.
to make . . . name--(So Isa 63:12; Sa2 7:23).
isa 63:15Here begins a fervent appeal to God to pity Israel now on the ground of His former benefits.
habitation of . . . holiness-- (Isa 57:15; Deu 26:15; Ch2 30:27; Psa 33:14; Psa 80:14).
zeal . . . strength--evinced formerly for Thy people.
sounding of . . . bowels--Thine emotions of compassion (Isa 16:11; Jer 31:20; Jer 48:36; Hos 11:8).
isa 63:16thou . . . father--of Israel, by right not merely of creation, but also of electing adoption (Isa 64:8; Deu 32:6; Ch1 29:10).
though Abraham . . . Israel--It had been the besetting temptation of the Jews to rest on the mere privilege of their descent from faithful Abraham and Jacob (Mat 3:9; Joh 8:39; Joh 4:12); now at last they renounce this, to trust in God alone as their Father, notwithstanding all appearances to the contrary. Even though Abraham, our earthly father, on whom we have prided ourselves, disown us, Thou wilt not (Isa 49:15; Psa 27:10). Isaac is not mentioned, because not all his posterity was admitted to the covenant, whereas all Jacob's was; Abraham is specified because he was the first father of the Jewish race.
everlasting--an argument why He should help them, namely, because of His everlasting immutability.
isa 63:17made us to err--that is, "suffer" us to err and to be hardened in our heart. They do not mean to deny their own blameworthiness, but confess that through their own fault God gave them over to a reprobate mind (Isa 6:9-10; Psa 119:10; Rom 1:28).
Return-- (Num 10:36; Psa 90:13).
isa 63:18people of . . . holiness--Israel dedicated as holy unto God (Isa 62:12; Deu 7:6).
possessed--namely, the Holy Land, or Thy "sanctuary," taken from the following clause, which is parallel to this (compare Isa 64:10-11; Psa 74:6-8).
thy--an argument why God should help them; their cause is His cause.
isa 63:19thine . . . never--rather, "We are Thine from of old; Thou barest not rule over them" [BARNES]. LOWTH translates, "We for long have been as those over whom Thou hast not ruled, who are not called by Thy name"; "for long" thus stands in contrast to "but a little while" (Isa 63:18). But the analogy of Isa 63:18 makes it likely that the first clause in this verse refers to the Jews, and the second to their foes, as English Version and BARNES translate it. The Jews' foes are aliens who have unjustly intruded into the Lord's heritage.