eka-i svarūpa doṅhe, bhinna-mātra kāya
ādya kāya-vyūha, kṛṣṇa-līlāra sahāya
eka-i—one; svarūpa—identity; doṅhe—both of Them; bhinna-mātra kāya—only two different bodies; ādya—original; kāya-vyūha—quadruple expansions; kṛṣṇa-līlāra—in the pastimes of Lord Kṛṣṇa; sahāya—assistance.
They are both one and the same identity. They differ only in form. He is the first bodily expansion of Kṛṣṇa, and He assists in Lord Kṛṣṇa's transcendental pastimes.
Balarāma is a svāṁśa expansion of the Lord, and therefore there is no difference in potency between Kṛṣṇa and Balarāma. The only difference is in Their bodily structure. As the first expansion of Godhead, Balarāma is the chief Deity among the first quadruple forms, and He is the foremost assistant of Śrī Kṛṣṇa in His transcendental activities.
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