The Mahabharata of Krishna-Dwaipayana Vyasa…
“ That Asura is now lying still in the observance of an ascetic penance of great austerity and, O king, the object he hath in view is sovereignty over the celestials as also of the three worlds. And, O king, having, obtained a boon from the Grandsire of all creatures, that Asura hath become incapable of being slain by the gods and Daityas and Rakshasas and Gandharvas. Slay though him, O king, and blessed be thou and let not thy heart turn to any other course. By slaying him thou wilt without doubt, achieve a great thing and thou wilt also obtain eternal and undying fame. ”
