Law sanctification and purification, so is defilement applied to the transgression of these precepts and the performance of disgraceful acts, as will be shown. Cleanliness in dress and body by washing and removing sweat and dirt is included among the various objects of the Law, but only if connected with purity of action, and with a heart free from low principles and bad habits. It would be extremely bad for man to content himself with a purity obtained by washing and cleanliness in dress, and to be at the same time voluptuous and unrestrained in food and lust. These are described by Isaiah as follows: "They that sanctify themselves and purify themselves in the gardens, but continue their sinful life, when they, are in the innermost [of their houses], eating swine's flesh, and the abomination, and the mouse" (Isa. lxvi. 17): that is to say, they purify and sanctify themselves outwardly as much as is exposed to the sight of the people, and when they are alone in their chambers and the inner parts of their houses, they continue their rebelliousness and disobedience, and indulge in partaking of forbidden food, such as [the flesh of] swine, worms, and mice. The prophet alludes perhaps in the phrase "behind one tree in the midst" to indulgence in forbidden lust. The sense of the passage is therefore this: They appear outwardly clean, but their heart is bent upon their desires and bodily enjoyments, and this is contrary to the spirit of the Law. For the chief object of the Law is to [teach man to] diminish his desires, and to cleanse his outer appearance after he has purified his heart. Those who wash their body and cleanse their garments whilst they remain dirty by bad actions and principles, are described by Solomon as "a generation that are pure in their own eyes, and yet are not washed from their filthiness; a generation, oh how lofty are their eyes!" etc. (Prov. xxx. 12-13). Consider well the principles which we mentioned in this chapter as the final causes of the Law: for there are many precepts, for which you will be unable to give a reason unless you possess a knowledge of these principles, as will be explained further on.
IT is also important to note that the Law does not take into account exceptional circumstances; it is not based on conditions which rarely occur. Whatever the Law teaches, whether it be of an intellectual, a moral, or a practical character, is founded on that which is the rule and not on that which is the exception: it ignores the injury that might be caused to a single person through a certain maxim or a certain divine precept. For the Law is a divine institution, and [in order to understand its operation] we must consider how in Nature the various forces produce benefits which are general, but in some solitary cases they cause also injury. This is clear from what has been said by ourselves as well as by others. We must consequently not be surprised when we find that the object of the Law does not fully appear in every individual; there must naturally be people who are not perfected by the instruction of the Law, just as there are beings which do not receive from the specific forms in Nature all that they require. For all this comes from one God, is the result of one act; "they are all given from one shepherd" (Eccles. xii. 11). It is impossible to be otherwise; and we have already explained (chap. xv.) that that which is impossible always remains impossible