Śrīmad-Bhāgavatam · Text 10.16.22
Who is speaking and story frame
कृष्णप्राणान्निर्विशतो नन्दादीन् वीक्ष्य तं ह्रदम् ।
प्रत्यषेधत् स भगवान् राम: कृष्णानुभाववित् ॥ २२ ॥
kṛṣṇa-prāṇān nirviśato
nandādīn vīkṣya taṁ hradam
pratyaṣedhat sa bhagavān
rāmaḥ kṛṣṇānubhāva-vit
Lord Balarāma then saw that Nanda Mahārāja and the other cowherd men, who had dedicated their very lives to Kṛṣṇa, were beginning to enter the serpent’s lake. As the Supreme Personality of Godhead, Lord Balarāma fully knew Lord Kṛṣṇa’s actual power, and therefore He restrained them.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.