'Sharpen' in the Bible

If one turn not, he will sharpen his sword; he hath bent his bow and made it ready,

They sharpen their tongues like a serpent; adders' poison is under their lips. Selah.

Sharpen the arrows; take the shields. Jehovah hath stirred up the spirit of the kings of the Medes; for his purpose is against Babylon, to destroy it; for this is the vengeance of Jehovah, the vengeance of his temple.