Mahabharata 3.139.4

3.139.4

athāvalokako'gacchadgṛhānekaḥ parāvasuḥ |
kṛṣṇājinena saṃvītaṃ dadarśa pitaraṃ vane || 4 ||

"Lomasa said, 'At that very time, the mighty king, Vrihadyumna, of high fortune, who was the Yajamana of Raivya, commenced a sacrifice. And the two sons of Raivya, Arvavasu and Paravasu, were engaged by that intelligent monarch, to assist him in the performance of the ceremony. And, O son of Kunti, taking the permission of their father, they two went to the sacrifice, while Raivya with Paravasu's wife remained in the hermitage. And it came to pass that one day, desirous of seeing his wife. Paravasu returned home alone. And he met his father in the wood, wrapped in the skin of a black antelope. And the night was far advanced and dark; and Paravasu, blinded by drowsiness in that deep wood, mistook his father for a straggling deer. And mistaking him for a deer, Paravasu, for the sake of personal safety, unintentionally killed his father. Then, O son of Bharata, after performing the funeral rites (of his father), he returned to the sacrifice and there addressed his brother saying, 'Thou wilt never be able to perform this task unassisted. I again, have killed our father, mistaking him for a deer. O brother, for me do thou observe a vow, prescribed in the case of killing a Brahmana. O Muni, I shall be able to perform this work (sacrifice), without any assistant.' Arvavasu said, 'Do thou then thyself officiate at this sacrifice of the gifted Vrihadyumna; and for thee will I, bringing my senses under perfect control, observe the vow prescribed in the case of slaying a Brahmana.'