Children are curious and inquisitive little beings, very capable of knowing spiritual things and having spiritual thoughts. They question the meaning of life and ponder on their purpose in the universe they are in, but without the complexity of the human limits. They dream of the impossibilities, even entering into imaginative worlds and universes of possibilities - a type of "heaven".
Children receive the concept of God without doubt. He simply exists in their world and somehow is at work in the universe they are living in. They see His wonders. They observe His beauty. Even in the midst of pain and darkness, they remain hopefully as long as God exists in their hearts and minds.
Hence, Jesus was clear to His disciples to never stumble children from their innocence and basal faith, instead to nurture them and direct them to the deeper knowledge of spiritual truths - Jesus Christ, Himself! He adds that they had to be like children to inherit the kingdom of God. To have the childlike faith-filled-innocence!
Many of us are in need to be like little children, again! We have become complicated and doubtful. We are skeptical of the goodness of God, and resist His will. Here, we are reminded again:
And he said: “Truly I tell you, unless you change and become like little children, you will never enter the kingdom of heaven" (Matt. 18:3).
Let us be childlike and learn from the innocence of children.