Dhp 239-241 · Impurity
Let a wise man blow off the impurities of his self, as a smith blows off the impurities of silver one by one, little by little, and from time to time. As the impurity which springs from the iron, when it springs from it, destroys it; thus do a transgressor's own works lead him to the evil path. The taint of prayers is non-repetition; the taint of houses, non-repair; the taint of the body is sloth; the taint of a watchman, thoughtlessness.