The Great Epic of the Bhārata dynasty 7.167.50

7.167.50

brāhmaṇaṃ vṛddhamācāryaṃ nyastaśastraṃ yathā munim |
ghātayitvādya rājyārthe mṛtaṃ śreyo na jīvitam || 50 ||

My preceptor had all along been under the impression that in consequence of my love for him, I could, (for his sake) abandon all,--sire, brother, children, wife and life itself. And yet moved by the desire of sovereignty, I interfered not when he was about to be slain. For this fault, O king, I have, O lord, already sunk into hell, overcome with shame. Having, for the sake of kingdom, caused the slaughter of one who was a Brahmana, who was venerable in years, who was my preceptor, who had laid aside his weapons, and who was then devoted, like a great ascetic, to Yoga, death has become preferable to me to life!'