“Hurry and come.” This may be the speaker (perhaps the prophet) exhorting God’s enemies to hurry to the battle, or it may even be the enemies exhorting each other to hurry, but in any case, the enemies of God are being exhorted to come to battle with God and His people. The enemy would be bloodthirsty and arrogant in their false confidence of victory and domination, but they are hurrying to their doom because he who fights with God fights a losing fight. The Egyptians did not win at the Exodus, the Canaanites did not win at the time of Joshua, and the enemy will not win at the Battle of Armageddon, their dead bodies will be food for the carrion birds (Rev. 19:19-21).
“Cause your mighty ones to come down there, O Yahweh.” The subjects shifts to someone, perhaps the prophet, speaking directly to God and requesting that He send down His mighty ones. This will happen when the heavenly armies come down and fight the Battle of Armageddon. [For more context of this, see commentary on Joel 3:9].