This is an elaboration of Vasiṣṭha’s statement that Viśvāmitra should be recognized as a brahmarṣi. “You will achieve the perfection of all aspects of a brahmarṣi” includes his ability to survive as a brāhmaṇa as well as teaching others worship, the scriptures and so on.

NOTE. In Caitanya-caritāmṛta Madhya 4.87 purport, Śrīla Prabhupāda talks about the activities of a genuine brāhmaṇa as follows: “A qualified brāhmaṇa must be expert in the occupational duties of a brāhmaṇa. His duties are mentioned as six brahminical engagements. Paṭhana means that a brāhmaṇa must be conversant with the Vedic scriptures. He must also be able to teach others to study the Vedic literatures. This is pāṭhana. He must also be expert in worshiping different deities and in performing the Vedic rituals (yajana). On account of this yajana, the brāhmaṇa, being the head of society, performs all the Vedic rituals for kṣatriyas, vaiśyas and śūdras. This is called yājana, assisting others in performing ceremonies. The remaining two items are dāna and pratigraha. The brāhmaṇa accepts all kinds of contributions (pratigraha) from his followers (namely, the kṣatriyas, vaiśyas and śūdras). But he does not keep all the money. He keeps only as much as required and gives the balance to others in charity (dāna).”