Cross reference
1 Corinthians 13:11
11 When I was a child, I made use of a child's language, I had a child's feelings and a child's thoughts: now that I am a man, I have put away the things of a child.
1 Corinthians 14:20
20 My brothers, do not be children in mind: in evil be as little children, but in mind be of full growth.
1 Corinthians 3:1-2
1 And the teaching I gave you, my brothers, was such as I was able to give, not to those who have the Spirit, but to those who are still in the flesh, even to children in Christ.
2 I gave you milk and not meat, because you were, then, unable to take it, and even now you are not able;
Galatians 4:1
1 But I say that as long as the son is a child, he is in no way different from a servant, though he is lord of all;
Ecclesiastes 11:10
10 So put away trouble from your heart, and sorrow from your flesh; because the early years and the best years are to no purpose.