Holiness, sanctity are often used without distinction to mean either the state or the character of one who is spiritually perfect or of something which is sacred or hallowed.
Holiness more often implies spiritual perfection, whether intrinsic and essential or acquired by effort than it does sacredness, although the latter implication is not uncommon.
Sanctity may be used either as denoting saintliness or the holiness attained by a saint or the quality of being sacred or by law and especially by natural or divine law immune from violation.