“Truly I tell you, unless you change and become like children, you will never enter the kingdom of heaven. Whoever becomes humble like this child is the greatest in the kingdom of heaven. ” (Mat 18:3-4) (NRSV)
Jesus emphasizes the importance of being like a child. However, when I observe children, I observe much that isn’t very pleasant. It is important to not confuse “child-like” with “childish” behaviors.
Childish behavior is rooted in selfishness which demands the immediate satisfaction of some perceived need. It is petty and impulsive, refusing to cooperate and throwing tantrums to punish anyone who opposes it. Child-like behavior arises from love which seeks the good of the other. It trusts the parental love which promotes great-heartedness.
This sort of trust doesn’t come easily. It calls for the obedience modeled by Jesus trusting his Father through his Passion, to Hell and back, and finally to the Resurrection.