“You must be able to distinguish between what is sacred (qodesh) and what is profane (chol), between what is clean (tahor) and what is unclean (tame’)” (Leviticus 10,10). In a fundamentally important essay on this subject, Paolo Sacchi asks himself whether the organisation of the words in this sentence should be understood in a parallel or chiastic manner. The answer is that one must opt for parallelism; the proportion is the following, sacred : impure = profane : pure. At a more ancient level, the sacred was perceived as if gifted with an intrinsic force that, just like impurity, acts of its own volition. As time passed things changed and the foundations of pure and impure became heteronomous. Yochanan ben Zakkay, the “legendary” founder of Rabbinic Judaism, is attributed the sentence, “a corpse does not defile nor does ash of the red heifer make levitically clean, but it is the decree of the Holy One” (see Numbers 19,1-16).