Arba was the forefather of Anak, and the city of Hebron was named Kiriath-Arba (City of Arba) after him. He is described in Joshua as 'the greatest man among the Anakim,' the race of giants that terrified the Israelite spies. Caleb's conquest of Kiriath-Arba and his victory over Anak's descendants became a defining act of faith.
The Anakim represented the most formidable human opposition to Israel's inheritance of the Promised Land. Their terrifying size had caused the faithless generation to despair (Numbers 13:33). Caleb's faithful conquest of Arba's city — at age 85, no less — stands as a monument to trusting God's promises over human obstacles. What fear had surrendered, faith reclaimed.