Christ as the Servant of Jehovah is the light of Israel and the glory of Jehovah rising upon Israel at His return (vv. 1-3). The entire earth today, including Israel, is under darkness. But when Christ comes as a Redeemer to Israel (Isa. 59:20), He will be their light to enlighten them, which light is the glory of God, i.e., God Himself in His glory (cf. Rev. 21:23; 22:5).