The Mahabharata - pg. 383

"You brahmanas, abandoning the legitimate functions of your varna and taking to the kshatirya profession of arms, have brought ruin to the princes. If you brahmana had not gone astray from the duties belonging to you by birth, the princes would not have been led to this destruction. You teach that non-killing is the highest dharma and that the brahmana is supporter and the nourisher of that dharma. Yet, you have rejected that wisdom which is yours by birth, and shamelessly undertaken the profession of killing. It was our misfortune that you descended to this sinful life."
Bhima taunting Drona