Defeating an opponent required taking the enemy’s (walled) cities (Joshua 6:1–27; 2 Samuel 12:26; 2 Kings 18:13). The phrase “the beloved city” echoes the words of Psalm 87:2: “The Lord loves the gates of Zion.” We are not to conclude, however, that the armies of the earth are physically marching to the literal city of Jerusalem (“Zion”). Jerusalem
stands for the church, the people of God among whom he dwells (1 Corinthians 3:16; Galatians 4:26). The “surrounding” is then a metaphorical effort to choke the (catholic) church of the Lord Jesus Christ and destroy her.
9 And they marched up over the broad plain of the earth and surrounded the camp of the saints and the beloved city, but fire came down from heaven and consumed them,