From which it appears that this prohibition of the eating of fat referred only to the fat of such beasts as were used for sacrifice. With these, however, the law was absolute, whether the animal was presented for sacrifice, or only slain for food. It held good with regard to these animals, even when, because of the manner of their death, they could not be used for sacrifice. In such cases, though the fat might be used for other purposes, still it must not be used for food.
The prohibition of the blood as food appears from xvii. 10 to have been absolutely universal; it is said, "Whatsoever man there be of the house of Israel, or of the strangers that sojourn among them, that eateth any manner of blood, I will set My face against that soul that eateth blood, and will cut him off from among his people."
The reason for the prohibition of the eating of blood, whether in the case of the sacrificial feasts of the peace-offerings or on other occasions, is given (xvii. 11, 12), in these words: "For the life of the flesh is in the blood: and I have given it to you upon the altar to make atonement for your souls: for it is the blood that maketh atonement by reason of the life. Therefore I said unto the children of Israel, No soul of you shall eat blood, neither shall any stranger that sojourneth among you eat blood."
And the prohibition is then extended to include not only the blood of animals which were used upon the altar, but also such as were taken in hunting, thus (ver. 13): "And whatsoever man there be of the children of Israel, or of the strangers that sojourn among them, which taketh in hunting any beast or fowl that may be eaten, he shall pour out the blood thereof, and cover it with dust," as something of peculiar sanctity; and then the reason previously given is repeated with emphasis (ver. 14): "For as to the life of all flesh, the blood thereof is all one with the life thereof: therefore I said unto the children of Israel, Ye shall eat the blood of no manner of flesh: for the life of all flesh is the blood thereof; whosoever eateth it shall be cut off."
And since, when an animal died from natural causes, or through being torn of a beast, the blood would be drawn from the flesh either not at all or but imperfectly, as further guarding against the possibility of eating blood, it is ordered (vv. 15, 16) that he who does this shall be held unclean: "Every soul that eateth that which dieth of itself, or that which is torn of beasts, whether he be home-born or a stranger, he shall wash his clothes, and bathe himself in water, and be unclean until the even. But if he wash them not nor bathe his flesh, then he shall bear his iniquity."
These passages explicitly state the reason for the prohibition by God of the use of blood for food to be the fact that, as the vehicle of the life, it has been appointed by Him as the means of expiation for sin upon the altar. And the reason for the prohibition of the fat is similar; namely, its appropriation for God upon the altar, as in the peace-offerings, the sin-offerings, and the guilt-offerings; "all the fat is the Lord's."
Thus the Israelite, by these two prohibitions, was to be continually reminded, so often as he partook of his daily food, of two things: by the one, of atonement by the blood as the only ground of acceptance; and by the other, of God's claim on the man redeemed by the blood, for the consecration of his best. Not only so, but by the frequent repetition, and still more by the heavy penalty attached to the violation of these laws, he was reminded of the exceeding importance that these two things had in the mind of God. If he eat the blood of any animal claimed by God for the altar, he should be cut off from his people; that is, outlawed, and cut off from all covenant privilege as a citizen of the kingdom of God in Israel. And even though the blood were that of the beast taken in the chase, still ceremonial purification was required as the condition of resuming his covenant position.