Śrīmad-Bhāgavatam · Text 4.5.24
Who is speaking and story frame
दृष्ट्वा संज्ञपनं योगं पशूनां स पतिर्मखे ।
यजमानपशो: कस्य कायात्तेनाहरच्छिर: ॥ २४ ॥
dṛṣṭvā saṁjñapanaṁ yogaṁ
paśūnāṁ sa patir makhe
yajamāna-paśoḥ kasya
kāyāt tenāharac chiraḥ
Then Vīrabhadra saw the wooden device in the sacrificial arena by which the animals were to have been killed. He took the opportunity of this facility to behead Dakṣa.
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