1 Samuel 13:19-22

Philistine ironworking

19 No metalworker was to be found anywhere in Israelite territory because the Philistines had said, "The Hebrews must not make swords and spears."
20 So every Israelite had to go down to the Philistines to sharpen their plowshares, mattocks, axes, and sickles.
21 The cost was two-thirds of a shekel for plowshares and mattocks, but one-third of a shekel for sharpening axes and for setting goads.
22 So on the day of the battle, no swords or spears were to be found in the possession of any of the troops with Saul and Jonathan, but Saul and his son Jonathan had them.