Out of the Mouths of Babes
Give me a world, to part for praise and sunder.
The brooks be bells; the winds, in caverns dumb,
Wake fife and flute and flageolet and voice;
The fire-shook earth itself be the great drum;
And let the air the region's bass out thunder;
The firs be violins; the reeds hautboys (oboes);
Rivers, seas, icebergs fill the great score up and under!
But rather dost thou hear the blundered words
Of breathing creatures; the music-lowing herds
Of thy great cattle; thy soft-bleating sheep;
O'erhovered by the trebles of thy birds,
Whose Christ-praised carelessness song-fills the deep;
Still rather a child's talk who apart doth hide him,
And make a tent for God to come and sit beside him.
-George MacDonald, Diary of an Old Soul, December 12,13
MacDonald hears creation alive with the sound of music; nature is singing the praises of her Creator. Brooks, storms, volcanoes, trees, rivers, seas, and icebergs "fill the great score up and under!" Cattle, sheep, birds and other breathing creatures fill out the chorus with "Christ-praised carelessness." But children, apart from all the rest of creation, in simple, playful trust "make a tent for God" and invite him to come and sit beside them.
David, in Psalm 8, says the same thing and much more. His poem begins with a startling contrast between the witness of the heavens and the chatter of little children.
O LORD, our Lord,
How excellent is Your name in all the earth,
Who have set Your glory above the heavens!
Out of the mouth of babes and nursing infants
You have ordained strength, because of Your enemies-
That You may silence the enemy and the avenger. 
David, like MacDonald, argues that God has revealed his glory and greatness in the skies, but the most persuasive answer to his critics is not the universe at large, as magnificent as it is, but the utterances of a little child: A toddler, accordingly, is a more compelling witness than the cosmos, for, unlike the unknowing universe, the smallest child can know and love God.
Jesus, you may recall, quoted this verse when the chief priests and scribes of Israel were scandalized by the children, running around in the temple and shouting "Hosanna ('Save, I pray!') to the Son of David." These little ones knew, as Israel's wise and learned men did not know--indeed could not know for they did not have the wisdom of a child--that Jesus was the long-awaited and much-loved Messiah.
Some of my most memorable moments as a parent were those when Carolyn and I knelt beside each child's bed at night and they, wearied by a long day of play, "made a tent for God" and invited Him to come and sit beside them. The simplicity of their love and faith as they poured out their prayers moved me deeply, often dispelling my doubt and fear and drawing me back to their simple trust in a tender and caring Friend.
"I praise you, Father, Lord of heaven and earth, because you have hidden these things from the wise and learned, and revealed them to little children." 
 The analogy, of course, is to child-play in which children make tents of blankets draped over chairs and tables and invite their playmates to sit in hiding beside them.
 Psalm 8:1,2
 Matthew 21:16
 Matthew 11:25