Atharvavedaparishishta 70.1.9

70.1.9

tatra śāntau prayuktāyāṃ kasya śāntiphalaṃ bhavet | nṛpo 'py adhārmikaḥ kuryād brahmaṇas tarpaṇaṃ purā ||

if the propitiatory rite is employed there, whose will the fruit of the propitiatory rite be? / Even an unrighteous king should first make an offering to the Brahman priest;