Jesus said unless we become as children, we cannot enter the kingdom of God. This does not mean we need to be childish, of course. It means we should be childlike. There’s a difference.
To be childlike means to approach the things of God with humility, trust, and faith that is simple and pure.
One way to understand and develop a childlike faith is to spend time with children. You enter their world and see things with their eyes. You communicate with them in words that they understand, as you also seek to understand what they say to you