Numbers 21:8-9
8
Yahweh said to Moses, "Make a fiery serpent, and set it on a standard: and it shall happen, that everyone who is bitten, when he sees it, shall live."
9
Moses made a serpent of brass, and set it on the standard: and it happened, that if a serpent had bitten any man, when he looked to the serpent of brass, he lived.