Everywhere else it appears, shanan is about weapons. Sharp arrows in Psalm 45:5 and Isaiah 5:28, the warrior's sharpened arrows of Psalm 120:4, the sharpened tongue. The picture is a blade or a point taken against a stone, pass after pass, until it can cut.

Then Deuteronomy 6:7 takes the weapons verb and hands it to parents: v'shinantam l'vanekha, you shall sharpen your children with these words. English Bibles render it teach them diligently, which keeps the duty and loses the picture. The command is repetition against the stone: when you sit in your house, when you walk by the way, when you lie down, when you rise. The setting is the home, the teacher is the parent, and the goal is a child with an edge.

Notice what the verb quietly rules out. Sharpening is not transferring conclusions; a stone does not hand the blade its edge, it draws the edge out of the blade by contact and repetition. The Torah's own pedagogy is not a class of experts dispensing meanings. It is the daily friction of the words themselves, in the mouth and in the house, until the person can cut.