Hebrews 5:12-14

Common(i) 12 For though by this time you ought to be teachers, you need someone to teach you again the first principles of God's word. You need milk, not solid food; 13 for every one who lives on milk is unskilled in the word of righteousness, for he is a babe. 14 But solid food is for the mature, for those who have their sense trained by practice to distinguish good from evil.