It is not inconsistent that a nail of the gallows and the tooth of a fox have been permitted to be used as cures: for these things have been considered in those days as facts established by experiment. They served as cures, in the same manner as the hanging of the peony over a person subject to epileptic fits, or the application of a dog's refuse to the swellings of the throat, and of the vapours of vinegar and marcasite to the swelling of hard tumours. For the Law permits as medicine everything that has been verified by experiment, although it cannot be explained by analogy. The above-named cures are permitted in the same way as the application of purgatives. Learn, reader, these noteworthy lessons from this my work, and keep them; "for they are a diadem of grace for thy head" (Prov. iv.).
We have explained in our large work that it is prohibited to round the corners of the head, and to mar the corners of the beard, because it was the custom of idolatrous priests. For the same reason, the wearing of garments made of linen and wool is prohibited: the heathen priests adorned themselves with garments containing vegetable and animal material, whilst they held in their hand a seal made of a mineral. This you find written in their books. The same is also the reason of the precept, "The woman shall not wear that which pertaineth unto a man" (Deut. xxii. 5). You find it in the book Tomtom, that a male person should wear coloured woman's dress when he stands before Venus, and a female, when standing before Mars, should wear a buckler and other armour. I think that this precept has also another reason; namely, that the interchange of dress creates lust and leads to immorality.
It is easily understood why it is prohibited to derive any benefit whatever from an idol. For sometimes a person buys it with the intention to break it, but keeps it, and it becomes a snare to him. Even if he broke it, recast it, and sold it to a heathen, he must not use the money which he received in exchange for the idol: because people frequently mistake accidental circumstances for essential causes: thus most people say of a certain person that he has become rich and wealthy after having dwelt in a certain house, or bought a certain animal or vessel; and that these things were a blessing to him. In the same way a person may be successful and make a good profit on the business in which he employed the money received for the idol; he might then think that the idol was the cause of his success, and that the blessing of the money received for it brought him the profit; he would then believe in the idol: a belief which is just the reverse of the chief object of the Law, as is clearly seen in every word of it. For this same reason, we are forbidden to turn to our use the covering of the idol, its offerings and vessels. We are thus guarded against the idea [of ascribing our success to idols]. In those days the belief in the stars was very strong; it was generally assumed that life and death, good and evil, depended on the stars. The Law employed therefore strong means, as covenant, witnesses, great oaths, and the abovementioned [blessings and] curses, in order to overthrow that belief. We are thus commanded to abstain from taking any portion of the idol, and deriving any benefit from it: and God tells us that if money received for idols be mixed with any person's property, it will bring loss and ruin to that property. This warning is contained in the words: "Neither shalt thou bring an abomination into thine house, lest thou be a cursed thing like it" (Deut. vii.
