If he does not relent, he will sharpen his sword; he will bend and string his bow. (NIV)
If a man does not turn and repent, [God] will whet His sword; He has strung and bent His [huge] bow and made it ready [by treading it with His foot]. (AMP)
If he turn not, he will whet his sword; he hath bent his bow, and made it ready. (KJV)