Bhagavad Gita Chapter 2.5
gurūn ahatvā hi mahānubhāvān
śreyo bhoktuḿ bhaikṣyam apīha loke
hatvārtha-kāmāḿs tu gurūn ihaiva
bhuñjīya bhogān rudhira-pradigdhān
It would be better to live in this world by begging than to live at the cost of the lives of great souls who are my teachers. Even though desiring worldly gain, they are superiors. If they are killed, everything we enjoy will be tainted with blood.