Passage
Chandogya Upanisad chup_5,22.2
san chandogya
samāne tṛpyati manas tṛpyati / manasi tṛpyati parjanyas tṛpyati / parjanye tṛpyati vidyut tṛpyati / vidyuti tṛpyantyāṃ yat kiṃca vidyuc ca parjanyaś cādhitiṣṭhatas tat tṛpyati / tasyānu tṛptiṃ tṛpyati prajayā paśubhir annādyena tejasā brahmavarcaseneti