O King, at the Rajasuya sacrifice, Maharaja Yudhisthira, the son of Maharaja Pandu, personally saw Sisupala merge into the body of the Supreme Lord, Krsna

Expressions researched:
"O King, at the Rajasuya sacrifice, Maharaja Yudhisthira, the son of Maharaja Pandu, personally saw Sisupala merge into the body of the Supreme Lord, Krsna"

Srimad-Bhagavatam

SB Canto 7

O King, at the Rājasūya sacrifice, Mahārāja Yudhiṣṭhira, the son of Mahārāja Pāṇḍu, personally saw Śiśupāla merge into the body of the Supreme Lord, Kṛṣṇa. Therefore, struck with wonder, he inquired about the reason for this from the great sage Nārada, who was seated there. While he inquired, all the sages present also heard him ask his question.

SB 7.1.14, Translation and Purport

O King, at the Rājasūya sacrifice, Mahārāja Yudhiṣṭhira, the son of Mahārāja Pāṇḍu, personally saw Śiśupāla merge into the body of the Supreme Lord, Kṛṣṇa. Therefore, struck with wonder, he inquired about the reason for this from the great sage Nārada, who was seated there. While he inquired, all the sages present also heard him ask his question.

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