"Iron sharpens iron, and one man sharpens another." (Proverbs 27:17)
The concept of “iron sharpening iron” obviously implies at least two pieces of iron. It would be impossible for one tool to become sharper without the presence of the other. Left isolated, both blades would be dull and quite useless. This simple Proverb illustrates an important biblical principle. God expects us to live and serve in a community of other believers (see Hebrews 10:25), and He desires for us to build loving and growing relationships with others (see 1 Thessalonians 2:8).