Mbh 5.37.4

“‘He who appropriates to himself the wife of one who hath confided in him; he who violates the bed of his preceptor; that Brahmana, O Bharata, who becomes the husband of a Sudra woman, or drinks wines; he who commendeth Brahmanas or becometh their master, or taketh away the lands that support them; and he who taketh the lives of those who yield asking for protection, are all guilty of the sin of slaying Brahmanas. The Vedas declare that contact with these requires expiation. He that accepts the teaching of the wise; he that is acquainted with the rules of morality; he that is liberal; he that eateth having first dedicated the food to the gods and Pitris; he that envieth none; he that is incapable of doing anything that injureth others; he that is grateful, truthful, humble and learned, succeedeth in attaining to heaven.