Srimad Bhagvata Mahapurana: Book 10: Chapter 26: Verses 14-25
A boy of seven years lifting up a big mountain-how inconceivable is this ! It is for this reason that our suspicion is aroused, 0 ruler of Vraja, with regard to your son (being God Himself). Nanda replied : (Pray,) hear my statement, 0 Gopas, which is (precisely) what the sage Garga told me concerning this boy; and let your suspicion about the child melt away. (Garga said:) Taking (diverse) forms indeed in each Yuga, this boy has manifested (in his body) three (different) colours, viz., white, red and yellow; this time he has assumed a dark complexion. Some time in the past this son of yours was born in the house of Vasudeva; (hence) the wise (who know this truth) will duly designate him as the glorious Vasudeva (son of Vasudeva). There are numerous names and forms of your son, conforming to his excellences and actions. I (alone) know them, not the commonalty. The delight of the cowherds, nay, of the entire Gokula, this boy will bring you happiness. By his help you will easily surmount all difficulties. Being protected and strengthened by him during a period of anarchy in former times, 0 lord of Vraja, pious souls, tormented by robbers, (eventually) conquered them. Enemies cannot overpower those highly blessed men who offer love to this boy, any more than demons can prevail over those whose cause has been espoused by Lord Visnu. Therefore, this son of yours, 0 Nanda, is a compeer of Lord Narayana in point of excellences, splendour, fame and glory, so that there is nothing to be wondered at his exploits.
Thus ends the twenty-sixth discourse in the first half of Book Ten of the great and glorious Bhagavata-Purana, otherwise known as the Paramahamsa-Samhita.