Charles Ellicott Commentary Isaiah 14:1

"For Jehovah will have compassion on Jacob, and will yet choose Israel, and set them in their own land: and the sojourner shall join himself with them, and they shall cleave to the house of Jacob." — Isaiah 14:1 (ASV)

For the Lord will have mercy on Jacob ... —The words imply a foresight of the return of the Israelites from exile, and therefore of the exile itself. The downfall of Babylon was certain, because without it the mercy of the Lord to Israel could not be manifested. The whole section is an anticipation of the great argument of Isaiah 40-66, and the question of its authorship stands or falls on the same grounds.

The strangers shall be joined with them ... —The thought is one specially characteristic of the later prophecies of Isaiah (Isaiah 44:5; Isaiah 55:5; Isaiah 56:3–6), but is prominent in the earlier also (Isaiah 2:2). In later Hebrew the same words came to be applied to the proselytes who are conspicuous in the apostolic age (Acts 2:10; Acts 6:5), and in them, as before in the adhesion and support of the Persian kings and satraps, and as afterwards in the admission of the Gentiles into the kingdom of the Christ, we may trace successive fulfilments of the prophet’s words.