Give me a few minutes to gather the scripture and I will prove you to be incorrect on that statement!
I Cor. 6:11
"And such were some of you: but ye are washed, but ye are sanctified, but ye are justified in the name of the Lord Jesus, and by the Spirit of our God."
This is positional sanctification at salvation! It is called past sanctification, were are sanctified by faith.
Rom. 15:16
"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."
This is the ongoing sanctification of the believer to bring him up to the level of his position in Christ. You notice here Paul says "being sanctified" by the Holy Spirit.
2 Cor. 3:18
" But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord."
This is the Holy Spirit transforming us into the image of Christ through sanctification.
And again, Rom. 8:29,
" For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren."
This again is the sanctification process of the Holy Spirit to conform us into the image of Christ, bringing us up to the position we have been placed by faith.
1Thes. 5:3
" And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ."
Here Paul is speaking of the ultimate sanctification at the "the coming of Christ" which is at the resurrection.
Phil. 3:20-21
"For our conversation is in heaven; from whence also we look for the Saviour, the Lord Jesus Christ:
Who shall change our vile body, that it may be fashioned like unto his glorious body, according to the working whereby he is able even to subdue all things unto himself."
Here Paul is telling us we will be transformed into the likeness of Christ.
I Cor. 15:51-53
"Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed,
In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
For this corruptible must put on incorruption, and this mortal must put on immortality."
This is our ultimate sanctification when we are made immortal as Christ is immortal, we will be perfect as He is perfect.