Jamieson, Fausset and Brown on Isaiah 45:22

22. Look ... and be ye saved--The second imperative expresses the result which will follow obedience to the first (Ge 42:18); ye shall be saved (Joh 3:14, 15). Nu 21:9: "If a serpent had bitten any man, when he beheld the serpent of brass he lived." What so simple as a look? Not do something, but look to the Saviour (Ac 16:30, 31). Believers look by faith, the eye of the soul. The look is that of one turning (see Margin) to God, as at once "Just and the Saviour" (Is 45:21), that is, the look of conversion (Psa 22:27).