¹⁰ If the iron is blunt, and one does not sharpen the edge, he must use more strength, but wisdom helps one to succeed.[1]

¹⁰ Using a dull ax requires great strength, so sharpen the blade. That's the value of wisdom; it helps you succeed.

¹⁰ If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct.