A file was a sharpening instrument of some sort (1 Samuel 13:21). Blunted tools were

sharpened on stones, as everywhere. Most translations except the NASB speak of sharpening

with a file, but the text of the verse is corrupt and the exact translation mere guesswork. But files

of some sort must of course have been used by metal-workers (Easton 1913). Proverbs indicates

that iron was used to sharpen objects, "Iron sharpens iron, So one man sharpens another"

(Proverbs 27:17 NASB). The Israelites may have discovered the file from the Philistines since

they went there to have their tools sharpened, "So all Israel went down to the Philistines, each to

sharpen his plowshare, his mattock, his axe, and his hoe" (1 Sa 13:20 NASB).