This is the third and last pericope, parallel to 57:14-21, that announces that God would deliver His people from the sin that plagued them as redeemed people (cf. 6:5). The section also closes the part of Isaiah that deals with the recognition of human inability (chs. 56-59).
"This is the ultimate development of the Divine Warrior motif in the Bible: God comes to destroy the final enemy of what he has created: not the monster Chaos, but the monster Sin."675
59:15b Though Israel was blind (v. 10), the Lord saw. He saw the true state of His people, as He sees everything. He saw that there was no justice in Israel or for Israel (vv. 9-15a).
59:16 God also saw that there was no human being who could mediate between Himself and His people, who could appeal effectively to Him for them (cf. 1 Tim. 2:5; Heb. 7:25; 1 John 2:1). So God Himself acted in power to deliver them, in faithfulness to His promises.
"In saying that God was astonished the prophet does not mean that God had been ignorant of the situation until He saw it and then this sight brought astonishment to Him. Rather, the language speaks of a genuine astonishment, which would express itself in displeasure and yet in compassion for His own to such an extent that He Himself acts."676
"Man's failure to avail himself of God's gracious provision to have a share in the restraint of wickedness and the promotion of righteousness through the ministery [sic] of intercession is a definite cause for divine astonishment."677
59:17 As a warrior preparing for battle, the Lord made ready to defend His people (cf. Eph. 6:13-17).
59:18 God would take vengeance on His enemies and on those forces that opposed His people. He would pay them back according to their dealings. While the context refers to deliverance from sin in a general sense, the reference to the coastlands suggests that the Lord will also defend and deliver Israel from Gentile opponents (at His second coming). Ultimately, of course, the Lord will subdue every enemy of His.
59:19 God's deliverance of His people will result in the whole world fearing Him for this display of His glory. His coming deliverance would be swift and forceful (cf. Rev. 6:15-17; 16:17-21). Water rushing down a wadi may be in view.
59:20 God would redeem His people, as the next of kin came to save the helpless widow. But it is His people who have turned away from their transgressions that He saves (cf. Rom. 11:25-27). They will have given up on their ability to deliver themselves or to secure deliverance from another source and will have turned to the Lord (cf. 55:6). That is the picture of "Jacob"that Isaiah gave in the preceding verses (vv. 9-15a; cf. 58:1, 14).678
59:21 In closing, God promised with a covenant promise that He would not withdraw His Spirit or His word from His people on whom He would place them (cf. Jer. 31:31-44). The Spirit would abide on His people forever, and His word would remain in their mouths so they could be the witnesses to Himself that He created them to be. Since this has not yet happened, it appears that it will happen at the Lord Jesus' second advent (v. 18).679Israel will witness to the greatness of Yahweh and will draw the nations to Him (cf. 2:2-3; 60:1-3). This is the purpose for which He will redeem them.
"The true people of God will ever be a witnessing people, faithfully proclaiming the truth of the Gospel in the power of the Holy Spirit."680
