Matthew 18:3-6 (New International Version)

³And he said: "I tell you the truth, unless you change and become like little children, you will never enter the kingdom of heaven. ⁴Therefore, whoever humbles himself like this child is the greatest in the kingdom of heaven.

 ⁵"And whoever welcomes a little child like this in my name welcomes me. ⁶But if anyone causes one of these little ones who believe in me to sin, it would be better for him to have a large millstone hung around his neck and to be drowned in the depths of the sea.