Isa 1:21

1:21 faithful. Godliness is demonstrated by perseverance, stability, and consistency in doing God’s will. Through the purifying process, the Lord will renew a remnant who will again constitute a “faithful city” (v. 26), because He is faithful (49:7; 55:3).

whore. A “whore” in religion is an idolater, someone who has forsaken God to serve idols (Jer. 2:20; 3:1; Hos. 2:2; 3:1; Ezek. 16:23–30). The sins listed (vv. 21–23) are all evidence that God’s people had forsaken Him.

justice . . . Righteousness. Justice means right relations between people. It is violated by murder, rebellion, stealing, and bribery (vv. 21–23). True justice will defend the cause of orphans and widows as much as the cause of those who can pay bribes and give rewards. The enemies of justice may even pass laws that facilitate their wrongdoing (10:1). Despite all such obstacles, God promises to restore righteousness to the earth (v. 26; 32:1; 33:5, 6; 42:1–4).