I have so often referred to the saying: The wisest can learn most from a child. And when someone who is himself able to look into the spiritual worlds has a child before him, with the stream that rises up into the spiritual world, it is as if — forgive the homely expression — he has in the child something like a telephone-line into the spiritual worlds. The spiritual world speaks through the child, but men are not aware of it. The wisest can learn most from a child. It is not the child that is speaking, but the angel is speaking out of the child.
Source: Rudolf Steiner – GA 127 – The Son of God and the Son of Man – Munich, February 11, 1911