sei nārāyaṇa kṛṣṇera svarūpa-abheda
eka-i vigraha, kintu ākāra-vibheda
sei—that; nārāyaṇa—Lord Nārāyaṇa; kṛṣṇera—of Lord Kṛṣṇa; svarūpa—original form; abheda—not different; eka-i—one; vigraha—identity; kintu—but; ākāra—of bodily features; vibheda—difference.
Nārāyaṇa and Śrī Kṛṣṇa are the same Personality of Godhead, but although They are identical, Their bodily features are different.
Link to this page: https://prabhupadabooks.com/cc/adi/28