of which is very dry, and certain water-fowl on account of their exceeding humidity.  In like manner certain fish lacking fins and scales were prohibited on account of their excessive moisture; such as eels and the like.  They were, however, allowed to eat ruminants and animals with a divided hoof, because in such animals the humors are well absorbed, and their nature well balanced:  for neither are they too moist, as is indicated by the hoof; nor are they too earthy, which is shown by their having not a flat but a cloven hoof.  Of fishes they were allowed to partake of the drier kinds, of which the fins and scales are an indication, because thereby the moist nature of the fish is tempered.  Of birds they were allowed to eat the tamer kinds, such as hens, partridges, and the like.  Another reason was detestation of idolatry:  because the Gentiles, and especially the Egyptians, among whom they had grown up, offered up these forbidden animals to their idols, or employed them for the purpose of sorcery:  whereas they did not eat those animals which the Jews were allowed to eat, but worshipped them as gods, or abstained, for some other motive, from eating them, as stated above (A. 3, ad 2).  The third reason was to prevent excessive care about food:  wherefore they were allowed to eat those animals which could be procured easily and promptly.

With regard to blood and fat, they were forbidden to partake of those of any animals whatever without exception.  Blood was forbidden, both in order to avoid cruelty, that they might abhor the shedding of human blood, as stated above (A. 3, ad 8); and in order to shun idolatrous rites whereby it was customary for men to collect the blood and to gather together around it for a banquet in honor of the idols, to whom they held the blood to be most acceptable.  Hence the Lord commanded the blood to be poured out and to be covered with earth (Lev. 17:13).  For the same reason they were forbidden to eat animals that had been suffocated or strangled:  because the blood of these animals would not be separated from the body:  or because this form of death is very painful to the victim; and the Lord wished to withdraw them from cruelty even in regard to irrational animals, so as to be less inclined to be cruel to other men, through being used to be kind to beasts.  They were forbidden to eat the fat:  both because idolaters ate it in honor of their gods; and because it used to be burnt in honor of God; and, again, because blood and fat are not nutritious, which is the cause assigned by Rabbi Moses (Doct.  Perplex. iii).  The reason why they were forbidden to eat the sinews is given in Gen. 32:32, where it is stated that “the children of Israel . . . eat not the sinew . . . because he touched the sinew of” Jacob’s “thigh and it shrank.”