The word ἁγιασμόη is translated in the A. V. both ‘sanctification' and ‘holiness;' but there is another word, ἁσγιωσύνη, always translated ‘holiness,' and it is well to see the distinction between them.
Both words may be traced to ἅγιος ‘holy,' but ἁγιωσύνη is holiness in its nature and quality. It occurs but three times: "the Spirit of holiness" in Rom. 1:4; the Christian should be "perfecting holiness in the fear of God," 2 Cor. 7:1; and Paul prayed for the Thessalonian saints that their hearts might be established "unblameable in holiness before God, even our Father, at the coming of the Lord Jesus Christ with all his saints." 1 Thess. 3:13.
ἁγιασμός. is more the result and activity of sanctification that produces holiness. It occurs in Rom. 6:19, 22; 1 Cor. 1:30; 1 Thess. 4:3, 4, 7; 2 Thess. 2:13; 1 Tim. 2:15; Heb. 12:14; 1 Pet. 1:2.
ἁγιότης, a kindred word to the above, also signifies ‘holiness' in its essence, perhaps in the most absolute way, ἁγιωσύς having a kind of middle place between ἁγιασμός and It occurs only in Heb. 12:10, unless it should be read in 2 Cor. 1:12, ‘holiness' instead of ‘simplicity,' as adopted by several Editors and the R. V. It is His holiness, the holiness of God Himself in its own nature, of which believers are to be partakers ― the end of all His gracious discipline.