Lord Krishna rejects the class system based on birth

 

I created the four divisions of human society based on aptitude and vocation. Though I am the author of this system of the division of labor, one should know that I do nothing directly and I am eternal. (See also 18.41) (4.13)
The division of human labor is also based on the qualities inherent in peoples’ nature or their make up. (See also 4.13) (18.41)
Those who have serenity, self control, austerity, purity, patience, honesty, transcendental knowledge, transcendental experience, and belief in God are labeled as intellectuals (Braahmans). (18.42)
Those having the qualities of heroism, vigor, firmness, dexterity, not fleeing from battle, charity, and administrative skills are called leaders or protectors (Kshatriyas). (18.43)
Those who are good in cultivation, cattle rearing, business, trade, finance, and industry are known as business men (Vaishyas). Those who are very good in service and labor type work only are classed as workers (Shudras). (18.44)