Kṛṣṇa's age, His beauty, His bugle, His flute, His conchshell and His pleasing attitude all provoke love in friendship for Him. His exceptional joking abilities, exhibited sometimes by His pretending to be a royal prince, or even the Supreme Personality of Godhead, also give impetus to devotees developing love for Kṛṣṇa in friendship.
Learned scholars have divided Kṛṣṇa's age into three periods: the age up through five years is called kaumāra, the age from the sixth through the tenth year is called paugaṇḍa, and the age from the eleventh through fifteenth year is called kaiśora. While Kṛṣṇa is spending His days as a cowherd boy, He is in the kaumāra and paugaṇḍa ages. In the kaiśora age, when Kṛṣṇa appeared in Gokula, He acted as a cowherd boy, and then, when He was sixteen, He went to Mathurā to kill Kaṁsa.