Brhadaranyaka-Upanisad, with Samkara's commentary 5.9

अयमग्निर्वैश्वाननरः पूर्ववदुपासनान्तरमयमग्निर्वैश्वानरः ।

ayamagnirvaiśvānanaraḥ pūrvavadupāsanāntaramayamagnirvaiśvānaraḥ /

Sanskrit only: no published translation is held for this verse.