Chapter XIV. How an unclean soul can neither give nor receive spiritual knowledge. But it is, as we have already said, impossible for a novice either to understand or to teach this. For if one is incapable of receiving it how can he be fit to pass it on to another? But if he has had the audacity to teach anything on these matters, most certainly his words will be idle and useless and only reach the ears of his hearers, without being able to touch their hearts, uttered as they were in sheer idleness and unfruitful vanity, for they do not proceed from the treasure of a good conscience, but from the empty impertinence of boastfulness. For it is impossible for an impure soul (however earnestly it may devote itself to reading) to obtain spiritual knowledge. For no one pours any rich ointment or fine honey or any precious liquid into a dirty and stinking vessel. For a jar that has once been filled with foul odours spoils the sweetest myrrh more readily than it receives any sweetness or grace from it, for what is pure is corrupted much more quickly than what is corrupt is purified. And so the vessel of our bosom unless it has first been purified from all the foul stains of sin will not be worthy to receive that blessed ointment of which it is said by the prophet: “Like the ointment upon the head, which ran down upon the beard of Aaron, which ran down upon the edge of his garment,” 1908 nor will it keep undefiled that spiritual knowledge and the words of Scripture which are “sweeter than honey and the honeycomb.” 1909 “For what share hath righteousness with iniquity? or what agreement hath light with darkness? or what concord has Christ with Belial?” 1910 1908     Ps. cxxxii. (cxxxiii.) 2 . 1909     Ps. xviii. (xix.) 11 . 1910     2 Cor. vi. 14, 15 .