First,to anoint is to apply,pour,rub,or smear with oil,ointment,etc.
In times of old,anointing oil is used in the official consecration of priests,kings,prophets,and vessels,to a holy or sacred use.It is also used for refreshing and for medicinal purposes.
The old testament ministers of God; priests,kings,and prophets were anointed to receive the Spirit of the LORD,that is,the power from above.
"Then Samuel took the horn of oil, and anointed him in the midst of his brethren: and the Spirit of the LORD came upon David from that day forward..." 1Sa 16:12-13.
These ministers of God are appointed to "process" the eradication of sins of God's people (Heb 9:22).The priests make's the sacrifices,the king enforces the will of God, and the prophets make known God's Will.With these 3 offices in place,man is able to receive blessings from God.And they do this as often as required; daily,monthly and yearly,and perpetually,using the blood of lambs,goats,bulls,etc...And this was then..
But now,Christ the anointed, is and carries our anointing!
He was/is the Lamb[Body we are baptised into (Eph 2:16), and the Blood of atonement,the "Communion of flesh & blood" we take of a new covenant. Christ declared by quoting Isaiah 61:1-2 that;
"The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel...". So now,everybody that believed and are baptized in Christ, IS IN CHRIST and IN THE SPIRIT of the LORD (Eph 2:18).Now therefore we are a brand new creation,able to process the eradication of sins.The 3 offices are combined in Christ,in whom we are!
We now carry the Spirit of Christ,the Anointed,everywhere we go!
This is just a summary,but nevertheless the truth,that the anointing is the Spirit of Christ,that is,The Holy Spirit permanently dwelling within us.Let us begin to operate as priests,kings and prophets of God.Shalom.
[For more read: Hebs 9:1-28,and Isa 61:1-7].