Sanctification is by the Holy Spirit

Lexham Survey of Theology Sanctification

Sanctification is the ongoing supernatural work of God to rescue justified sinners from the disease of sin and to conform them to the image of his Son: holy, Christlike, and empowered to do good works.

Romans 15:15–16 KJV 1900

Nevertheless, brethren, I have written the more boldly unto you in some sort, as putting you in mind, because of the grace that is given to me of God, That I should be the minister of Jesus Christ to the Gentiles, ministering the gospel of God, that the offering up of the Gentiles might be acceptable, being sanctified by the Holy Ghost.

1 Peter 1:2 KJV 1900

Elect according to the foreknowledge of God the Father, through sanctification of the Spirit, unto obedience and sprinkling of the blood of Jesus Christ: Grace unto you, and peace, be multiplied.

Titus 3:5 KJV 1900

Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost;

2 Thessalonians 2:13 KJV 1900

But we are bound to give thanks alway to God for you, brethren beloved of the Lord, because God hath from the beginning chosen you to salvation through sanctification of the Spirit and belief of the truth:

Romans 8:12–14 KJV 1900

Therefore, brethren, we are debtors, not to the flesh, to live after the flesh. For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live. For as many as are led by the Spirit of God, they are the sons of God.