2 Kings 6:17

Lord, I pray thee, open his eyes The eyes of his body were open, and with them he saw the danger; Lord, said the prophet, open the eyes of his faith, and the eyes of his mind, that with them he may see the protection we are under, may see the invisible guard of heavenly beings which encompass and defend us. Angels, whether they be purely spiritual, or clothed with some material vehicle, it is allowed, cannot be seen by mortal eyes: and, therefore, as the prophet himself would not have seen them, unless God by a miracle had rendered them visible to his eyes, so he requests of God that, for the causes above mentioned, he would vouchsafe to his servant the same privilege. And behold, the mountain was full of horses and chariots of fire Fire is both dreadful and devouring: that power, which was engaged for Elisha, could both terrify and consume the assailants. Round about Elisha The mountains, which were full of these fiery chariots and horses, were round about the city, and therefore round about Elisha, who was within it: or he saw, as if he, Elisha, was in the midst of a glorious camp of angels, who defended him so that nothing could penetrate and break through unto him. “The opening of our eyes,” says Henry, “will be the silencing of our fears. In the dark we are most apt to be frightened. The clearer sight we have of the sovereignty and power of heaven, the less we shall fear the calamities of this earth.”