KJV : If the iron <01270> be blunt <06949> (8765), and he do not whet <07043> (8773) the edge <06440>, then must he put <01396> (8762) to more strength <02428>: but wisdom <02451> [is] profitable <03504> to direct <03787> (8687).NASB : If the axe is dull and he does not sharpen \i1 its\i0 edge, then he must exert more strength. Wisdom has the advantage of giving success.NASB# : If<518> the axe<1270> is dull<6949> and he does not sharpen<7043> <I>its</I> edge<6440>, then he must exert<1396> more strength<2428>. Wisdom<2451> has the advantage<3504> of giving<3787> success<3787>.