SB 11.4.17
haṁsa-svarūpy avadad acyuta ātma-yogaṁ
dattaḥ kumāra ṛṣabho bhagavān pitā naḥ
viṣṇuḥ śivāya jagatāṁ kalayāvatīrṇas
tenāhṛtā madhu-bhidā śrutayo hayāsye
dattaḥ kumāra ṛṣabho bhagavān pitā naḥ
viṣṇuḥ śivāya jagatāṁ kalayāvatīrṇas
tenāhṛtā madhu-bhidā śrutayo hayāsye
Word for word:
haṁsa-svarūpī — assuming His eternal form of the swan incarnation; avadat — He spoke; acyutaḥ — the infallible Supreme Personality of Godhead; ātma-yogam — self-realization; dattaḥ — Dattātreya; kumāraḥ — the Kumāra brothers, headed by Sanaka; ṛṣabhaḥ — Ṛṣabhadeva; bhagavān — the Lord; pitā — father; naḥ — our; viṣṇuḥ — Lord Viṣṇu; śivāya — for the welfare; jagatām — of all the world; kalayā — by His secondary personal expansions; avatīrṇaḥ — descending to this world; tena — by Him; āhṛtāḥ — were brought back (from the depths of Pātālaloka); madhu-bhidā — by the killer of the demon Madhu; śrutayaḥ — the original texts of the Vedas; haya-āsye — in the horse-headed incarnation.
Translation:
The infallible Supreme Personality of Godhead, Viṣṇu, has descended into this world by His various partial incarnations such as Lord Haṁsa [the swan], Dattātreya, the four Kumāras and our own father, the mighty Ṛṣabhadeva. By such incarnations, the Lord teaches the science of self-realization for the benefit of the whole universe. In His appearance as Hayagrīva He killed the demon Madhu and thus brought the Vedas back from the hellish planet Pātālaloka.
Purport:
It is stated in the Skanda Purāṇa that the Lord of the universe, Hari Himself, once appeared in the form of a young brahmacārī named Kumāra and spoke transcendental knowledge to Sanat-kumāra.