Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 3

Sanskrit:

गतिस्मितप्रेक्षणभाषणादिषुप्रिया: प्रियस्य प्रतिरूढमूर्तय: ।असावहं त्वित्यबलास्तदात्मिकान्यवेदिषु: कृष्णविहारविभ्रमा: ॥ ३ ॥

ITRANS:

gati-smita-prekṣaṇa-bhāṣaṇādiṣupriyāḥ priyasya pratirūḍha-mūrtayaḥasāv ahaṁ tv ity abalās tad-ātmikānyavediṣuḥ kṛṣṇa-vihāra-vibhramāḥ

Translation:

Because the beloved gopīs were absorbed in thoughts of their beloved Kṛṣṇa, their bodies imitated His way of moving and smiling, His way of beholding them, His speech and His other distinctive features. Deeply immersed in thinking of Him and maddened by remembering His pastimes, they declared to one another, “I am Kṛṣṇa!”

Purport:

Spontaneously, the gopīs began moving like Kṛṣṇa: they smiled as He would smile, glanced boldly as He would and spoke as He would. The gopīs were completely absorbed in the existence of Kṛṣṇa and mad with love at their sudden separation from Him, and thus their dedication to Him attained absolute perfection.