Hebrews 1:7
"And of the angels he saith, Who maketh his angels spirits, and his ministers a flame of fire."
Cross References (ranked by relevance)
Who maketh his angels spirits; his ministers a flaming fire:
Are they not all ministering spirits, sent forth to minister for them who shall be heirs of salvation?
And Elisha prayed, and said, LORD, I pray thee, open his eyes, that he may see. And the LORD opened the eyes of the young man; and he saw: and, behold, the mountain was full of horses and chariots of fire round about Elisha.
And it came to pass, as they still went on, and talked, that, behold, there appeared a chariot of fire, and horses of fire, and parted them both asunder; and Elijah went up by a whirlwind into heaven.
And the angel answered and said unto me, These are the four spirits of the heavens, which go forth from standing before the LORD of all the earth.
A fiery stream issued and came forth from before him: thousand thousands ministered unto him, and ten thousand times ten thousand stood before him: the judgment was set, and the books were opened.