"Iron sharpeneth iron; so a man sharpeneth the countenance of his friend," Proverbs 27:17 tells us. God uses Christian friendships to help His children grow in grace and stay true to Christ. But our twenty-first-century Western culture values individualism, busyness, and selfishness--qualities that do not encourage deep, long-lasting, satisfying friendships. The authors guide us through a practical survey of biblical and historical friendships,...