tam sasapa kulacaryah
na ksatra-bandhuh sudras tvam
tam—him (Prsadhra); sasapa—cursed; kula-acaryah—the family priest, Vasistha; krta-agasam—because of committing the great sin of killing a cow; akamatah—although he did not want to do it; na—not; ksatra-bandhuh—the family member of a ksatriya; sudrah tvam—you have behaved like a sudra; karmana—therefore by your fruitive reaction; bhavita—you shall become a sudra; amuna—because of killing the cow.
Although Prsadhra had committed the sin unknowingly, his family priest, Vasistha, cursed him, saying, “In your next life you shall not be able to become a ksatriya. Instead, you shall take birth as a sudra because of killing the cow.”
It appears that Vasistha was not free from tamo-guna, the mode of ignorance. As the family priest or spiritual master of Prsadhra, Vasistha should have taken Prsadhra’s offense very lightly, but instead Vasistha cursed him to become a sudra. It is the duty of a family priest not to curse a disciple but to give him relief through the performance of some sort of atonement. Vasistha, however, did just the opposite. Therefore Srila Visvanatha Cakravarti Thakura says that he was durmati; in other words, his intelligence was not very good.
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