The Hebrew verb chadad (H2300) means to be sharp or to be keen, referring to the sharpness of a blade, a point, or a tongue. It is related to the noun chad (H2299, sharp) and the noun chedvah. The word appears in Proverbs and Ezekiel in both literal and figurative contexts — sharp swords, sharp arrows, and the sharp tongue of the wicked.
Sharpness in the Old Testament carries both positive and negative connotations. A sharpened sword in the hand of a soldier is a tool of God's justice (Ezekiel 21:9-11); a sharpened tongue in the mouth of the wicked is a weapon of destruction (Psalm 64:3). Proverbs 27:17 uses the related concept with profound wisdom: 'As iron sharpens iron, so one person sharpens another.' This verse reveals the God-designed purpose of close fellowship — believers are meant to chadad one another, making each other keener, more precise, more effective for God's purposes. Spiritual sharpness comes through the Word of God (Hebrews 4:12: 'sharper than any double-edged sword') and through honest, loving community.