At that time the disciples came to Jesus saying, “Who is the greatest in the kingdom of heaven?” He called a child, had him stand among them, and said, “I tell you the truth, unless you turn around and become like little children, you will never enter the kingdom of heaven! Whoever then humbles himself like this little child is the greatest in the kingdom of heaven. And whoever welcomes a child like this in my name welcomes me.

 - Matthew 18, NET