Shatapatha Brahmana 11.2.6.7

11.2.6.7

sa yatprāśitramavadyati yathaiva tatprājāpaterāviddhaṃ nirakṛntannevamevaitasyaitadyadveṣṭitaṃ yadgrathitaṃ yadvaruṇyaṃ tanniṣkṛntanti sa vidyādyathaiva tatprajāpaterāviddhaṃ nirakṛntannevameva ma idaṃ yadveṣṭitaṃ yadgrathitaṃ yadvaruṇyaṃ tanniṣkṛntantīti

And when he cuts off the fore-portion,---even as there they cut out what was injured in Pragâpati, so do they now thereby cut out what in this (body) is clogged and hardened, and affected by Varuna let him know that, as there they cut out what was injured in Pragâpati, so they now cut out what in him is clogged and hardened and affected by Varuna.