Whoever does not put himself under the kingdom of God like a little child, will not come into it at all.

The kingdom of God

And when Jesus saw it, he was angry, and said to them, Let the little children come to me, and do not keep them away; for of such is the kingdom of God. Truly I say to you, Whoever does not put himself under the kingdom of God like a little child, will not come into it at all.
Mark 10:14-15