Hebrews 5:11-14 - Advanced Teaching Hindered By Immaturity
11 Concerning whom we have much to say, and that which is difficult to explain, because you have become dull of hearing. 12 For you who ought on account of the time to be teachers, have need that one should teach you again what are the first rudiments of the oracles of God, and have need of milk and not solid food. 13 For every one that partakes of milk is unskilful in the word of righteousness, for he is a babe; 14 but solid food is for the perfect, having their perceptive faculties exercised by practice to distinguish both good and evil.