Mahabharata 12.78.32

12.78.32

bhīṣma uvāca |
tasmāddvijātīnrakṣeta te hi rakṣanti rakṣitāḥ |
āśīreṣāṃ bhavedrājñāṃ rāṣṭraṃ samyakpravardhate || 32 ||

"Bhishma continued, 'Thou shouldst, therefore, protect the Brahmanas. Protected by thee, they will protect thee in return. Their blessings, O king, would surely descend upon kings of righteous behaviour. For the sake of righteousness, those Brahmanas that are not observant of the duties of their order should be chastised and separated (into a distinct class) from their superiors. A king who conducts himself in this way towards the people of his city and the provinces, obtains prosperity here and residence in heaven with Indra.'"