“The spirit of Lord Yahweh.” Here in Isaiah 61:1, God’s gift of holy spirit is called “the spirit of the Lord Yahweh.” In this verse, the “of” indicates the genitive case, which can be a genitive of possession, i.e., “the spirit belonging to Lord Yahweh,” or it can be a genitive of origin, “the spirit from Lord Yahweh,” or it can combine both meanings and be an amphibologia (double entendre) since both meanings are true.
In this verse, God foretells that the Messiah will have God’s gift of holy spirit upon him. God placed His holy spirit upon Jesus to spiritually empower him so that he could do mighty works. God put His gift of spirit, sometimes called “holy spirit,” upon people to give them spiritual power (cp. Num. 11:17-29; Judges 3:10; 6:34; 11:29; 1 Sam. 10:6, 10; 16:13; 1 Chron. 12:18; 2 Chron. 15:1; Micah 3:8), and Jesus needed God’s gift of holy spirit to have spiritual power just like the leaders and prophets of the Old Testament did. Jesus received the gift of holy spirit at His baptism and had it upon him when he started his ministry (Luke 4:18). Other verses that say God was going to put holy spirit upon the Messiah are Isaiah 11:2, 42:1 and 61:1.
Christians get spiritual power when they get the gift of holy spirit (Acts 1:8), but sadly, most believers are not taught how to use that spiritual power like Christ and the apostles did. [For more on the holy spirit being a gift from God that empowered people to do wonderful things for God, see Appendix 6, “Usages of Spirit”].