Hebrews 5:12-14

For you should now be teaching others, if we look at the time, yet you need to be taught again which are the first elements of the oracles of God and are become such as have need of milk, and not of strong food. For any one that uses milk is not qualified in the word of righteousness, for he is a babe. But strong food belongs to those that are perfect, even those who by reason of use have their senses exercised to discern both good and evil.