SB 10.46.23

manye kṛṣṇaṁ ca rāmaṁ ca
 prāptāv iha surottamau
surāṇāṁ mahad-arthāya
 gargasya vacanaṁ yathā
Synonyms: 
manye — I think; kṛṣṇam — Kṛṣṇa; ca — and; rāmam — Balarāma; ca — and; prāptau — obtained; iha — on this planet; sura — of demigods; uttamau — two of the most elevated; surāṇām — of the demigods; mahat — great; arthāya — for a purpose; gargasya — of the sage Garga; vacanam — the statement; yathā — as.
Translation: 
In my opinion, Kṛṣṇa and Balarāma must be two exalted demigods who have come to this planet to fulfill some great mission of the demigods. Such was foretold by Garga Ṛṣi.