In childhood, you think the sun (or the moon) revolves around you. "Daddy, why is the sun following us everywhere we go?
In adulthood, you know that you revolve around the sun.
In childhood, you think that large objects far away are small objects. (With pointer and thumb only a centimeter apart) "That airplane is only this big!"
In adulthood, you know that large objects far away only appear small because you are so small and so far away.
In childhood, you think that not-so-big things are really big.
In adulthood, you return to those so-big-as-a-child things and realize they are not so big.
"...until we all attain to the unity of the faith and of the knowledge of the Son of God, to mature manhood, to the measure of the stature of the fullness of Christ, so that we may no longer be children..." Ephesians 4:13-14