Mbh 12.65.1b

[205] Those men who disregard all wholesome restraints and who are too much attached to the pursuit of worldly objects are said to be of the nature of brutes. They are compelled to act with justice by the exercise of kingly duties. Those duties, therefore, are said to be the foremost of all. That course of conduct which has been prescribed for Brahmanas who follow the three Vedas, and those modes of life that have been laid down for Brahmanas, should, before everything else, be observed by every Brahmana. If a Brahmana acts otherwise, he should be punished like a Sudra. The duties of the four modes of life and the ritual prescribed in the Vedas, O king, should ever be followed by a Brahmana. Know that he has no other duties. For a Brahmana acting otherwise, a Kshatriya should not make any arrangement for sustenance. His religious merit grows in consequence of his acts. A Brahmana, indeed, is like Dharma's self. That Brahmana who is employed in acts that are not laid down for him, deserves no respect. If not engaged in his proper acts, he should not be trusted. These are the duties that appertain to the several orders. Kshatriyas should take care of them so that their observance may be improved. Even these are the duties of Kshatriyas. For these reasons also, kingly duties and no other, are the foremost of all. They are, as I believe, the duties of heroes, and they that are heroes are foremost in practising them.'