Hebrews 5:12 TLB

[12] You have been Christians a long time now, and you ought to be teaching others, but instead you have dropped back to the place where you need someone to teach you all over again the very first principles in God's Word. You are like babies who can drink only milk, not old enough for solid food. And when a person is still living on milk it shows he isn't very far along in the Christian life, and doesn't know much about the difference between right and wrong. He is still a baby Christian!