Come As Little Children
It's common in evangelical circles to hear the parallel passages in Matthew 19:, Mark 10:, and Luke 18: interpreted to mean that the faith of children is somehow superior to the faith of adults in its purity or lack of hypocrisy. Is that what Jesus intended to teach? It seems to me that that idea has more to do with the Romanticism of Russeau than with Christ's teaching.
If we look at other instances where Jesus seized upon the top-of-mind topic of the moment for didactic purposes, we find that He nearly always, if not always, used them for one purpose: to teach what the kingdom of Heaven, or of God, is like. The same is true of His parables. It seems to have been His chief, perhaps almost His only, topic. That's not surprising, since He needed to prepare His disciples to live in the kingdom, and since it's inperceptible to the flesh, that is to the senses.