SB 8.8.34
sa vai bhagavatah saksad
visnor amsamsa-sambhavah
dhanvantarir iti khyata
ayur-veda-drg ijya-bhak
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
This person was Dhanvantari, a plenary portion of a plenary portion of Lord Visnu. He was very conversant with the science of medicine, and as one of the demigods he was permitted to take a share in sacrifices.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Srila Madhvacarya remarks:
tesam satyac calanartham
harir dhanvantarir vibhuh
samartho ’py asuranam tu
sva-hastad amucat sudham
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.