Another of the verses of Malkiyos recited on Rosh Hashana, the ibn Ezra explains this verse as follows: G-d is the exclusive “King of Israel” when they are in their land and not subject to any foreign power subjugating them. He is “their Redeemer” when they are in exile. At all times, He is “L-rd of hosts,” the hosts of Heaven testifying to His role as King.