The boon that Vishvamitra prayed for was that he should be permitted to become a Brahmana. Brahmana, the grandfather of all the worlds, said to him-"So be it.'
स तु ववे वरं राजन् स्यामहं ब्राह्मणास्त्विति॥ तथेति चाब्रवीद् ब्रह्मा सर्वलोकपितामहः।