I still am not sure what he was trying to say.

many years ago when I was a young man, my grandfather gave me a pocket knife.  I was kind of excited because I didn't have a knife of my own and I really thought having a knife was cool.  Also, my grandfather never had paid much attention to me and wasn't much for gift giving.  After he handed it to me, I bright-eyed over the yellow handle and silver tips before putting my thumbnail into the slot on the blade.  I opened the blade and immediately noticed there was no sharp edge to the blade.  It was so dull that it was apparent it was never meant to be sharp.  It was more spatula than knife.  I said, "thank you".  He said, "son, a dull knife is more dangerous than a sharp knife".  I remember trying to smile.