2 Kings 6:16-18 (New International Version)
16 "Don't be afraid," the prophet answered. "Those who are with us are more than those who are with them."
17 And Elisha prayed, "O LORD, open his eyes so he may see." Then the LORD opened the servant's eyes, and he looked and saw the hills full of horses and chariots of fire all around Elisha.
18 As the enemy came down toward him, Elisha prayed to the LORD, "Strike these people with blindness." So he struck them with blindness, as Elisha had asked.