Numbers 21
8 Ref And Jehovah said unto Moses, Make thee a fiery serpent, and set it upon a standard: and it shall come to pass, that every one that is bitten, when he seeth it, shall live.
9 Ref And Moses made a serpent of brass, and set it upon the standard: and it came to pass, that if a serpent had bitten any man, when he looked unto the serpent of brass, he lived.