Numbers 21:7-9

Young's Literal Translation

⁷ and the people come in unto Moses and say, `We have sinned, for we have spoken against Jehovah, and against thee; pray unto Jehovah, and He doth turn aside from us the serpent;' and Moses prayeth in behalf of the people.

⁸ And Jehovah saith unto Moses, `Make for thee a burning [serpent], and set it on an ensign; and it hath been, every one who is bitten and hath seen it -- he hath lived.

⁹ And Moses maketh a serpent of brass, and setteth it on the ensign, and it hath been, if the serpent hath bitten any man, and he hath looked expectingly unto the serpent of brass -- he hath lived.