Perhaps a parable can help answer this question. There was once a king that had a son who was his heir to the throne. The king wanted this son be learned, an artist and a man of spirit. Therefore he encouraged him to apply himself in academics and music and art lessons. Unfortunately the son went in different directions. He despised his studies and sat around idly. We all know idleness leads to foolishness and this led the man down a steep slope to bad deeds. When the king saw his son slipping the king called him back and he had no other choice but to give him a plot of land that his son would have to work on in order to sustain himself.
Then king’s son became a farmer actually and saw blessing in his handiwork. He was very proud of the vegetables that grew in his patch of land. People who didn’t know the situation were puzzled as to why the son of the king would spend his time farming and how the king allowed this. But people who knew the situation agreed this was the best thing for the young man at this point.
So too about our topic: When man was created he was chosen by G-d to have a leading spiritual role in the world. At that time he was not permitted to eat animals he could only eat from the earth’s produce as the verse says: “Behold I’ve given you all the grasses that seed on the face of the earth and all trees that have fruit with seeds to plant, they should be food for you.” (Genesis 1, 29)
However when man lost his lofty spiritual level to the point of doing theft and murder and people did as they saw fit, they were then permitted to eat animal meat for 2 reasons:
1. In order for man to realize his elevation above nature and his intrinsic holiness. Indeed he is permitted to kill and eat the rest of the animals so they’ll realize, animals can be killed but people can’t, it is forbidden.
2. Eating animal meat will prevent cannibalism. The base need to eat meat can be fulfilled by eating animal meat.
This permission to eat meat only began after the great flood as the verse says: “And G-d blessed Noah and his children and He told them…and your fear will be upon all the animals of the land and the birds of the sky. All that crawls on earth and all the fish of the sea are given into your hands. All crawling living things you may eat just like the vegetables and grasses I’ve given you all of them.” (Genesis 9, 2)
These 2 reasons make it a mistake to try and prohibit the consumption of meat. As long as humanity hasn’t reached its destined purpose at the time of the Messiah the above dangers still exist.
When we, the Jewish nation became “a kingdom of priests and a holy nation” when we received the Torah, most animals became prohibited to us for consumption. The list of prohibited animals includes animals of prey or those who live from eating carrion and animal carcasses and all those animals that live in dirt and are sustained from contamination. We were only permitted to eat animals with gentle traits whose bodies and inner beings are gentle, so as not to harm our Jewish body and soul. Even these animals were only permitted to us when ritually slaughtered which cases no pain to the animal.
In those birds and undomesticated animals permitted to us after ritual slaughtering we are commanded to cover over the blood to show it is as if we are embarrassed with this deed of killing animals which reminds us we haven’t yet reached the lofty level that G-d wants us and all of humanity to reach. (Domestic animals need not have their blood covered as the act of killing them is not as ‘shameful’ as killing the undomesticated animals that need to be trapped from the wild.
One exception to this idea however is chickens that grow up in a coop which still need to have their blood covered.
Though we can eat the meat after ritual slaughter and covering the blood we are still prohibited from eating the animal’s blood. Blood is the essence of the animal’s life force and consuming it leads to cruelty. That is why we are commanded to remove the blood from the meat through salting it in order to make it kosher or roasting it in fire to remove the blood.
However, when the world reaches its completion at the time of the redemption both man and animal will return to their original sublime state. (See Rabbi Chaim Vital’s words in the ‘Gate of Mitzvoth’ about Adam’s lofty level before sinning by eating from the tree of knowledge and the great loss of his level upon sinning which lowered his level and that of all of creation including the animal kingdom too). We will then be prohibited again from eating animal meat as before. But today we must recognize our lack of attaining this level and not prohibit eating meat. If we persist in prohibiting meat consumption at this point it will lead to cruelty in mankind to one another.
It is well known that there are people who were very compassionate to animals and ruthlessly killed their fellow man without batting an eyelash. The Nazis were a case in point. Even in Israel there are right now people who would be happy to see people mauled and killed by feral dogs than to allow these dogs and the danger they pose to be destroyed. This debate actually went up to the Israeli Supreme Court.
This phenomenon is brought down in a verse: “Those who slaughter man kiss calves” (Hosea 13, 2). The psychological reason for this is that there are 2 opposing powers in the psyche of man:
1, the inclination to destroy and harm anyone or anything that disagrees with his wishes and 2, the conscience that wants us to be goodhearted and have compassion and do kindness with one another. Therefore, someone who ends up using his inclination for destruction against his fellow man will calm his conscience by exaggerated compassion for animals. For the rabbit and cat aren’t a threat to him as a fellow man may be. So they are the worthy recipients for his misplaced compassion while at the same time his fellow man bears the brunt of his wrath. Someone who is overly concerned with the welfare of animals above what the Torah requires is liable to discover he is cruel to his fellow man.