Isaiah 42:4

“He shall not fail, &c.] For want of strength to go through the work of redemption: or, “grow dim”f810 and dark, as a lamp for want of oil, or as the wick of a candle ready to go out. Hence the Septuagint version, “he shall shinef811”; in the glory of his person, as the Son of God; in the fulness of his grace, as Mediator, which shall never fail; and in the hearts of his people by his Spirit; and in his Gospel published to the world: nor be discouraged; at the number, power, and menaces of his enemies, he had to grapple with, sin, Satan, the world, and death: or, nor be brokenf812; with the weight of all the sins of his people upon him; and with a sense of divine wrath; and with the whole…”

“fail--faint; man in religion may become as the almost expiring flax-wick (Isa 42:3), but not so He in His purposes of grace. discouraged--literally, "broken," that is, checked in zeal by discouragements (compare Isa 49:4-5). ROSENMULLER not so well translates, "He shall not be too slow on the one hand, nor run too hastily on the other." judgment--His true religion, the canon of His judgments and righteous reign. isles . . . wait, &c.--The distant lands beyond sea shall put their trust in His gospel way of salvation. Mat 12:21 virtually gives the sense, with the inspired addition of another aspect of the same thing, "In his name shall the Gentiles trust" (as "wait for" here means, Isa 30:18).…”

“He shall not fail - He shall not be weak, feeble, or disheartened. However much there may be that shall tend to discourage, yet his purpose is fixed, and he will pursue it with steadiness and ardor until the great work shall be fully accomplished. There may be an allusion in the Hebrew word here (יכהה yı̂kheh) to that which is applied to the flax (כהה kēhâh); and the idea may be that he shall not become in his purposes like the smoking, flickering, dying flame of a lamp. There shall never be any indication, even amidst all embarrassments, that it is his intention to abandon his plan of extending the true religion through all the world. Such also should be the fixed and determined purposes…”

“'Till - 'Till he has established his law or doctrine, among the nations of the earth. Isles - The countries remote from Judea, shall gladly receive his doctrine. Isaiah 42:5”

“42:4 distant lands: The nations long for justice and for instruction on bringing it about. In this regard the servant is like Moses, to whom the law was given. However, the servant is greater in that he extends justice beyond Israel to all the nations.”

“shall not: Isa 9:7, Isa 49:5-10, Isa 52:13-15, Isa 53:2-12; Joh 17:4, Joh 17:5; Heb 12:2-4; Pe1 2:22-24 discouraged: Heb. broken and the isles: Isa 42:12, Isa 2:2-4, Isa 11:9-12, Isa 24:15, Isa 24:16, Isa 41:5, Isa 55:5, Isa 60:9, Isa 66:19; Gen 49:10; Psa 22:27, Psa 72:8-11, Psa 98:2, Psa 98:3; Mic 4:1-3; Zac 2:11; Rom 16:26; Co1 9:21 Isaiah 42:5”

“The figures in Isa 42:3 now lead to the thought that the servant of God will never be extinguished or become broken Himself. "He will not become faint or broken, till He establish right upon earth, and the islands wait for His instruction." As יכהה (become faint) points back to כהה פשׁתה (the finat or glimmering wick), so ירּוץ must point back to רצוּץ קנה (the bruised or broken reed); it cannot therefore be derived from רוּץ (to run) in the sense of "He will not be rash or impetuous, but execute His calling with wise moderation," as Hengstenberg supposes, but as in Ecc 12:6, from רצץ = ירץ (Ges. 67, Anm. 9), in the neuter sense of infringetur (will break). His zeal will not be extinguished,…”