Revākhaṇḍa ascribed to the Vāyupurāṇa (RKV) 232.31

232.31

yaścedaṃ śṛṇuyānnityaṃ purāṇaṃ devabhāṣitam /
brāhmaṇo vedavānbhūyātkṣatriyo vijayī bhavet //

And whoever constantly listens to this purāṇa spoken by the gods— / if a Brahmin, he becomes learned in the Vedas; if a kṣatriya, he becomes victorious;