2 Kings 2:10 (KJV)

And Elijah took his mantle, and wrapped it together, and smote the waters, and they were divided hither and thither, so that they two went over on dry ground.

And it came to pass, when they were gone over, that Elijah said unto Elisha, Ask what I shall do for thee, before I be taken away from thee. And Elisha said, I pray thee, let a double portion of thy spirit be upon me.

And he said, Thou hast asked a hard thing: nevertheless, if thou see me when I am taken from thee, it shall be so unto thee; but if not, it shall not be so.

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 Elisha saw it, and he cried, My father, my father, the chariot of Israel, and the horsemen thereof. And he saw him no more: and he took hold of his own clothes, and rent them in two pieces.