And if we avoid it, then we did not avoid it because of its impurity, for its being impurity is a legal ruling , and it may be neither intellectually filthy nor impure . The thing that He requires for itself does not require the existence of its essence, nor is it possible to estimate the existence of its essence. Whether it is non-existent or present, the ruling on it is the same, whether it is pure or not, it does not matter whether it is in the knowledge of God or whether it exists in His essence. Do you not see that what is possible has outweighed its existence? On its non-existence or its non-existence on the basis of its existence, and yet the ruling of possibility is removed from it, and that possibility is obligatory for it in and of itself, just as the referral to the impossible is obligatory for it in and of itself, just as the obligation for the obligatory is obligatory for it in and of itself, so the intelligible obligation applies to the obligatory for itself. Likewise, the ruling on the possible and the impossible does not change its ruling even if the ranks differ.
( Chapter on the ruling on animal urine )