Jesus and children

I just read an interesting article on the web about Jesus and children.
It has got me thinking.
Here is the start of it. The entire article may be read at Crosswalk.com.

Jesus & the Children: Pondering Children as Pride Detectors
John Piper
Desiring God

"One thing to watch for when assessing a person's spiritual fitness for ministry is how he or she relates to children. Put a child in the room and watch. This is what Jesus did to make his point. Children are the litmus paper to expose the presence of pride."