Christ accomplishes salvation for His people (Isa. 52:13–53:12; John 6:39–40; Heb. 10:18), and we appropriate that salvation through faith alone, which faith itself is the gift of God to His elect through the regeneration of the Holy Spirit (John 3:1–8; Eph. 2:8–9). But God the Holy Spirit works in and through the preaching of His Word to bring us to faith (1 Cor. 1:21; 2 Tim. 3:14–15; 1 Peter 1:22–25). Moreover, He works in and through His Word to keep us in faith, encouraging us to persevere and warning us lest we fall away. These encouragements and warnings are God’s means of keeping us in His grace, for the Spirit always works in the hearts of the elect to make them heed these encouragements and warnings so that they never fall away fully and finally from Christ (Isa. 55:10–11; Mark 4:1–20; John 16:13; Heb. 6:9–12; 12:1–2; James 5:19–20; 1 John 2:19).
So, even though Jesus accomplished salvation for His people once and for all, He continues to work by the Spirit through His Word to preserve us in faith while we remain on this side of glory. Thus, He warns us through Isaiah, as well as the other prophets and Apostles, and we who know Jesus truly take these warnings seriously. We search our hearts to see whether we are guilty of the charges, and if we are, we repent and cling to Christ alone even tighter and persevere. All those who have been saved will persevere in faith and repentance until the end of their lives, and only those who persevere in faith and repentance until the end of their lives have been saved (Matt. 10:22b; Rom. 8:38–39).
Therefore, we think on the warnings of Isaiah 59:14–21 soberly. We see that there will be times when the upright are hated in public, righteousness is ridiculed, and those who affirm God’s Word are granted no place at society’s table (v. 14). At these times, fallen society is particularly clear in its rejection of truth, and it makes prey out of those who flee evil and serve the Lord—it attacks the just and praises the unjust, approving deeds of darkness (Rom. 1:28–32). At such times, we might feel like giving up and going along with the crowd, but that would be the worst mistake we could ever make. A day is coming when God will no longer withhold His wrath but suit up for battle. He will repay His enemies according to their deeds, not graciously as He did on the cross, conquering us by bringing us over to His side. Instead, the Lord will conquer His enemies on that day by giving them the full measure of His just wrath (Isa. 59:15b–19).