Bṛhadāraṇyaka Upaniṣad ("Great Forest Teaching") 1.3.7

1.3.7

atha hemamāsanyaṃ prāṇamūcustvaṃ na udgāyeti tatheti tebhya eṣa prāṇa udagāyatte viduranena vai na udgātrātyeṣyantīti tamabhidrutya pāpmanāvivyatsansa yathāśmānamṛtvā loṣṭo vidhvam̐setaivam̐ haiva vidhvam̐ samānā viṣvañco vineśustato devā abhavanparāsurā bhavatyātmanā parāsya dviṣanbhrātṛvyo bhavati ya evaṃ veda

Then they said to the breath in the mouth: 'Do thou sing for us.' 'Yes,' said the breath, and sang. The Asuras knew: 'Verily, through this singer they will overcome us.' They therefore rushed at him and pierced him with evil. Now as a ball of earth will be scattered when hitting a stone, thus they perished, scattered in all directions. Hence the Devas rose, the Asuras fell. He who knows this, rises by his self, and the enemy who hates him falls.