Krishna loves and favours the cows and the Brahminical persons . Why ?
Many reasons ,
Certainly the cows and Brahminical persons are seen to be benevolent,  peaceful, tolerant , and always full of abundance in this sense , in the case of the Brahminical order , they are overflowing with good wishes , and the best of knowledge is distributed  freely by them  to one and all , at all  times  , indeed they are well wishers of  all of  humanity and every living beings . They fully understand the consciousness condition and why  it is certain types of consciousness arise, which can be both harmful or beneficial .

In the case of the cow , they show the example to humanity ,   giving off a peaceful healing aura , indeed, persons with mental vulnerabilities can be  greatly benefited in their association . In fact, cow hugging has become a useful addition to various therapies. This feeling of  deep peacefulness  the cows  exudes and the example the cows show in  submissive service to anyone , along with  living peacefully  just by eating grass that nature provides , generates their  wonderfully gentle persona , undisturbed , easily approachable . They produce excess milk and are easily milked undisturbed .  The benefits of milk to the consciousness are spoken of in the Vedas , milk  helps  consciousness  and finer brain tissues are said to develop by regularly drinking it ,  particularly useful for the sensitivity of  spiritual awareness . We can note there are  benefits of being in the association of highly qualified persons , who give off positive good energies ,  cows also possess these special benedictory qualities that are very beneficial to us humans . Krishna has made such arrangements , by His grace , He  speaks in the Bhagavad Gita about different types of consciousness , and it appears Krishna has specifically blessed the Brahminical persons and the cows so they can bless us .
It’s also mentioned in the Vedas that killing both Brahminical persons or cows is the most heinous and sinful act .
To kill a giving merciful person is indeed demoniac .
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