In the Torah portion of Acharei-Mot, we learn the obligation of "kisui ha'dam," to cover the blood produced from slaughtering (Leviticus 17:13).
Commentators take a number of different approaches to explain the reason for this mitzvah. Rambam argues that this ritual is meant to distance Jewish practice from pagan blood rites. He suggests that pagans would collect the blood after slaughter and eat the animal's meat while sitting around the blood; for Rambam, we pour out and cover the blood to distance ourselves from these pagan practices of using the blood to connect with spirits.
"...they imagined that in this manner the spirits would come to partake of the blood which was their food, whilst the idolaters were eating the flesh; that love, brotherhood and friendship with the spirits were established, because they dined with the latter at one place and at the same time (Guide for the Perplexed 3:46)."
Rabbi Shimshon Raphael Hirsch took a very different approach. He suggested that we cover the blood in order to distance ourselves from the animalistic essence of human beings. Animals kill other animals without thought, but, as humans, we must be more elevated. According to Hirsch, we refrain from consuming the blood to demonstrate that we are not animals and to prevent the life force of the animal (the blood) from entering into our life force.
The Sefer ha'Chinuch (187) suggests that we cover the blood in order to refine our character. He argues that if one were to become accustomed to merely slaughtering animals and immediately consuming them while their blood still lies before us on the ground, we might become insensitive, and even violent. The Torah requires us to cover the blood, according to the Sefer ha'Chinuch, in order to cultivate compassionate virtue.
Each of these approaches acknowledges that there is something very sensitive about killing animals and how it affects people. There seems to be a traditional discomfort with the way other societies have handled this recklessly. Even further, there is an implicit demand that one be connected with one's food source. Jewish law, and its underlying values, completely rejects the norms of the factory farming industry as it exists today.
Some may see these rules around covering the blood as a basicmanner of food preservation, since it was evident even in ancient times that bloody meat spoiled quickly, whereas meat drained of blood and salted could be preserved. Other cultures follow parallel principles, such as the Muslim halalrule of draining blood, and the old European, and then American, custom (from colonial times) of smoking and salting meat. However, the Jewish sages obviously had more in mind than a meat inspection code. Similarly, blood-borne diseases, such as rabies, malaria, hepatitis B and HIV, lead modern healthcare workers to be very careful, but this knowledge (and even HIV) is a modern development; as recently as the mid-19th century, the predominant belief was that foul odors (miasma theory) were more of a contributing factor to disease than blood.
There must be another reason. One clue is the continuing human revulsion toward blood. Scientists estimate that about 15 percent of people feel weak or even faint at the sight of blood. It even has a scientific name, blood-injury phobia.
One reason, perhaps, for this phobia is that humans have always been cognizant that blood meant injury, and very often, death. (Even during the Civil War, wounds to arms and legs often resulted in amputation, and wounds to the torso were almost always fatal.) They could also see that animal blood had the same appearance as human blood, and modern science has confirmed this similarity.
Humans and most vertebrates share many components, including red blood cells (erythrocytes), white blood cells (leukocytes, such as lymphocytes that are necessary for the immune system) and platelets (which allow for blood clotting to stop bleeding). Thus, most animals have the same red-blood cell antigens that result in blood types such as O, A or B, as well as the Rh antigen.
Human blood is also more than 80 percent water (the plasma that contains the white and red blood cells and platelets is almost all water), further confirming the similarity with animal blood. Thus, humans perceive a connection between any kind of animal blood and death.
I would suggest that the primary reason the Torah is telling us to cover the blood is because we feel shame. In fact, the Talmud teaches that this mitzvah is from where the very concept of "bizui mitzvah," shaming the Torah, is derived (Shabbat 22a). We look at the blood of the animal pouring off the knife, dripping down our hands and filling a pool upon the earth, and we feel profound embarrassment because we realize what we've done. That blood looks identical to our own, and we realize our own mortality and the fragility of our existence. All we can do in that moment is rush to cover it up.
This is yet another attempt from the Torah to move us toward vegetarianism. The Torah did everything possible, short of prohibiting the consumption of meat, to make it very difficult to eat meat and to distance ourselves from death. While those who are not yet vegetarians are no longer engaging in the traditional ritual of shame -- pouring out the blood before consuming meat -- to be reminded of the death that has been caused and of our own mortality, we might all take more steps to learn about the harsh realities of mass production of food today and how it is harming human health, animal welfare and the environment.
ON Scripture -- The Torah is a weekly Jewish scriptural commentary, produced in collaboration with