Clay is fashioned into vessels; it is on their empty hollowness that their use depends. Doors and windows are cut out to make a dwelling, and on the empty space within, its use depends. Thus, while the existence of things may be good, it is the non-existence in them that makes them serviceable.
Holiness, as taught in the Scriptures, is not based upon knowledge on our part. Rather, it is based upon the resurrected Christ in-dwelling us and changing us into His likeness.