In Old Testament times, it was common practice to anoint officials: prophets, priests, and kings. But even the patriarchs (Abram, Isaac, Jacob) are called God’s “anointed ones” in Ps. 105:15.
The ritual of anointing with oil is, first of all, a sign of dedication to God. In Gen. 28:18 we read that Jacob poured oil on the top of a stone, declaring that “this stone, which I have set up for a pillar, shall be God’s house (Beth-El).” Decades later, the LORD reminds him: “You anointed a pillar, you made a vow to me; come back.” (Gen. 31:13)
Later, God commands the ritual anointing of the Tabernacle and its furniture (Ex. 40:9). They are not only dedicated to God, but receive a special status: “so that it may become holy”. The most holy things were not to be touched by anyone but the priests, on penalty of death: they have been lifted out of the common world and now belong to God.
The first time we read in detail about the anointing of a person, it is Aaron the High Priest and his sons. (Ex. 28:41) They, too, become holy. Only this ritual qualifies them to function as mediators between the LORD and his people. “Their anointing shall admit them to a perpetual priesthood throughout their generations.” (Ex. 40:15)
The holiness of anything or anyone anointed was especially shown by David, when he refused to kill his enemy Saul, because: “Who can put out his hand against the LORD’s anointed and be guiltless?” (1 Sam. 26:9; see also 24:6, 26:11; 2 Sam. 1:14)
Anointing belonged to the taking up of a sacred office: of prophet, priest, or king. But behind that specific office lies the more basic idea that the whole person is consecrated, dedicated to the LORD, and therefore holy.
Finally, anointing is not only connected to dedication and holiness, but also to the Holy Spirit. When David was anointed, we read that from that moment on, the Holy Spirit took hold of him. (1 Sam. 16:13) The anointing with the Holy Spirit means that a person is dedicated, set apart as holy, but also equipped with God’s own Spirit to do God’s work in the world.
In Isaiah 61:1, the prophet says: “The Spirit of the Lord GOD is upon me, because the LORD has anointed me”—a text which applies especially to Jesus Christ, Jesus who is the Anointed, who not only represents God in this world but is God’s very presence. Anointing was rare in the Old Testament, singling out people to prefigure the coming of the Messiah, the ultimate Anointed one. But now that he has come, the anointing with the Spirit is for all who believe: “But you have been anointed by the Holy One…” (1 John 2:20)