Śrīmad-Bhāgavatam · Text 10.13.18
Who is speaking and story frame
तत: कृष्णो मुदं कर्तुं तन्मातृणां च कस्य च ।
उभयायितमात्मानं चक्रे विश्वकृदीश्वर: ॥ १८ ॥
tataḥ kṛṣṇo mudaṁ kartuṁ
tan-mātṝṇāṁ ca kasya ca
ubhayāyitam ātmānaṁ
cakre viśva-kṛd īśvaraḥ
Thereafter, just to create pleasure both for Brahmā and for the mothers of the calves and cowherd boys, Kṛṣṇa, the creator of the entire cosmic manifestation, expanded Himself as calves and boys.
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