Rigveda 8.44.21

अ॒ग्निः शुचि॑व्रततम॒: शुचि॒र्विप्र॒: शुचि॑: क॒विः ।शुची॑ रोचत॒ आहु॑तः॥

agniḥ śucivratatama: śucirvipra: śuci: kaviḥ |śucī rocata āhutaḥ ||

Our plain-language meaning of this verse is waiting for scholar review.