John was born a stranger to the world of children who used to amuse themselves, as he was serious all the time. Most children took delight in torturing animals whereas, he was merciful to them. He fed the animals from his food until there was nothing left for him, and he just ate fruit or leaves of trees.
John loved reading since childhood. When he grew up, Allah the Exalted called upon him: "0 John! Hold fast to the Scripture (The Torah)." And We gave him wisdom while yet a child. Surah 19: 12