25:1–5. Speaking in the first person Isaiah described the situation which will exist when the kingdom is established on the earth. The prophet ascribed praise to the Lord’s name (His revealed character) for His marvelous acts of judgment (vv. 2–3) and deliverance vv. 4–5). God’s judgment on the city, representative of the world (cf. 24:12–13), will cause peoples from ruthless nations to honor and revere God.
This will fulfill the promise given Abraham that all the world’s nations will be blessed through Israel (Gen. 12:3). The theme of Gentiles knowing and worshiping God in the kingdom is common in the prophets (see, e.g., Isa. 2:3; 11:9; 49:7; 56:6; 66:20–21; Zech. 14:16–19; Mal. 1:11).
When the Lord will establish His kingdom on the earth, a reversal of fortunes will occur (Isa. 25:4–5). The poor (dal, “feeble, weak, helpless”) and the needy (’eḇyôn, “oppressed”) will be rescued and the ruthless will be stilled. God’s care for the poor and the needy is mentioned many times in the Old and New Testaments. The reversal of fortunes, in which those who depend on God are helped and those who depend on themselves are judged, is a major theme of Scripture (e.g., 1 Sam. 2:1–10; Jas 5:1–6). The ruthless in their harsh treatment of others are like a storm and the oppressive desert heat. But God’s judgment on them will be like a cloud that suddenly covers the sun, thus limiting its heat.
(2) Effects of the coming kingdom (25:6–12). The deliverance that the Lord will bring will include the wiping away of death (vv. 6–8), the rejoicing of His people (v. 9), and judgment on His enemies (vv. 10–12).
John A. Martin, “Isaiah,” in The Bible Knowledge Commentary: An Exposition of the Scriptures, ed. J. F. Walvoord and R. B. Zuck, vol. 1 (Wheaton, IL: Victor Books, 1985), 1073.