Jamieson, Fausset and Brown on Isaiah 45:14

14. The language but cursorily alludes to Egypt, Ethiopia, and Seba, being given to Cyrus as a ransom in lieu of Israel whom he restored (Is 43:3), but mainly and fully describes the gathering in of the Gentiles to Israel (Ac 2:10, 11; 8:27-38), especially at Israel's future restoration (Is 2:2; 14:1, 2; 19:18-22; 60:3-14; 49:23; Psa 68:31; 72:10, 11).

labour--wealth acquired by labor (Jr 3:24).

Sabeans ... of stature--the men of Meroe, in Upper Egypt. Herodotus (3.30) calls the Ethiopians "the tallest of men" (see on Is 18:2; 1Ch 11:23).

thee--Jerusalem ("my city," Is 45:13).

in chains--(Psa 149:8). "The saints shall judge the world" (1Co 6:2) and "rule the nations with a rod of iron" (Zec 14:12-19; Re 2:26, 27). The "chains," in the case of the obedient, shall be the easy yoke of Messiah; as "the sword of the Spirit" also is saving to the believer, condemnatory to the unbeliever (Joh 12:48; He 4:12; Re 19:15).

God is in thee--(Jr 3:19).