New Defender's Study Bible Notes
68:18 ascended on high. As quoted in the New Testament (Ephesians 4:8), this passage is applied to Christ in His ascension after He first descended into Hades (“the lower parts of the earth”), then “ascended up far above all things” (Ephesians 4:9-10).
68:18 captivity captive. When Christ ascended up from hades to heaven, He “proclaimed liberty to the captives” (Isaiah 61:1) and carried them with Him up to Paradise. The captives refer to those who had died, having faith in the coming Redeemer. The picture corresponds to that of a returning conqueror, bringing back with him those who had been captives in an enemy land.