Joshua 12:20 lists King Reba of the land of Hermon among the defeated kings by the Israelites under Moses and Joshua's leadership. This verse highlights the fulfillment of God's promise to give the land of Canaan to the Israelites. It serves as a reminder of God's faithfulness in delivering victory to His people as they followed His commands. The detailed account of the conquered territories demonstrates the precision and completeness of God's fulfillment of His covenant with Israel. Overall, Joshua 12:20 showcases the sovereignty of God in establishing His chosen nation in the Promised Land.