sa vai bhagavataḥ sākṣād
dhanvantarir iti khyāta
saḥ—he; vai—indeed; bhagavataḥ—of the Supreme Personality of Godhead; sākṣāt—directly; viṣṇoḥ—of Lord Viṣṇu; aṁśa-aṁśa-sambhavaḥ—incarnation of the plenary portion of a plenary portion; dhanvantariḥ—Dhanvantari; iti—thus; khyātaḥ—celebrated; āyuḥ-veda-dṛk—fully conversant in the medical science; ijya-bhāk—one of the demigods eligible to share the benefits of sacrifices.
This person was Dhanvantari, a plenary portion of a plenary portion of Lord Viṣṇu. He was very conversant with the science of medicine, and as one of the demigods he was permitted to take a share in sacrifices.
Śrīla Madhvācārya remarks:
Dhanvantari, who was carrying the jug containing nectar, was a plenary incarnation of the Supreme Personality of Godhead, but although he was very strong, the asuras were able to take the jug of nectar from his hands.
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