Revākhaṇḍa ascribed to the Vāyupurāṇa (RKV) 228.6

228.6

śreṣṭhaṃ hi vihitaṃ prāhurdharmakarma yudhiṣṭhira /
taireva kārayettasmānnottamairnādhamairapi //

For they say religious duty performed by these is best, O Yudhiṣṭhira; / therefore one should have it done by them alone, neither by higher nor by lower ones.