If one is trained to honor and worship the cows and brahmanas, he is actually civilized. The worship of the Supreme Lord is recommended, and the Lord is very fond of the cows and brahmanas (namo brahmanya-devaya go-brahmana-hitaya ca). In other words, a civilization in which there is no respect for the cows and brahmanas is condemned. One cannot become spiritually advanced without acquiring the brahminical qualifications and giving protection to cows. Cow protection insures sufficient food prepared with milk, which is needed for an advanced civilization. One should not pollute civilization by eating the flesh of cows. A civilization must do something progressive, and then it is an Aryan civilization. Instead of killing the cow to eat flesh, civilized men must prepare various milk products that will enhance the condition of society. If one follows the brahminical culture, he will become competent in Krsna consciousness.

Srila Prabhupada's purport to Srimad-Bhagavatam 6.18.52.