Śatapatha Brāhmaṇa ("of a hundred paths") 4.2.2.15

4.2.2.15

tadu brūyādeva bhūyaḥ | iṣa ūrje pavata iti vṛṣṭyai tadāha yadāheṣa ityūrja iti yo vṛṣṭādūrgraso jāyate tasmai tadāhādbhya oṣadhībhyaḥ pavata iti tadadbhyaścauṣadhībhyaścāha dyāvāpṛthivībhyām pavata iti tadābhyāṃ dyāvāpṛthivībhyāmāha yayoridaṃ sarvamadhi subhūtāya pavata iti sādhave pavata ityevaitadāha

Let him, nevertheless, say this more, 'For sap and pith he becometh pure,'--by saying 'for sap' he means to say 'for rain;' and 'for pith' he says with a view to that pith or juice which springs from rain;--'for the waters and plants he becometh pure,' this he says for the waters and plants;--'for heaven and earth he becometh pure,' this he says for those two, heaven and earth, whereon this All rests;--'for well-being he becometh pure,' whereby he means to say 'for good.'