Vasudeva
Sage Kashyapa is said to have incarnated as Vasudeva, the father of Krishna due to a curse of the god Brahma. Once, the sage performed a yajna (a Vedic sacrifice) in his hermitage for the welfare of the world. Kashyapa sought the help of the god Varuna for the offerings of milk, ghee etc. Varuna granted the sage a holy cow which will provide the offerings on the condition that the sage returns the same to Varuna after the sacrifice. After completing the sacrifice after several days, Kashyapa was overcome with greed, realizing the miraculous power of the cow, and refused to return the cow arguing that whatever is offered to a Brahmin like Kashyapa should never be sought back, and whoever does that would turn out to be a sinner.