Numbers 21:6-9

So GOD sent poisonous snakes among the people; they bit them and many in Israel died. The people came to Moses and said, “We sinned when we spoke out against GOD and you. Pray to GOD; ask him to take these snakes from us.” Moses prayed for the people. GOD said to Moses, “Make a snake and put it on a flagpole: Whoever is bitten and looks at it will live.” So Moses made a snake of fiery copper and put it on top of a flagpole. Anyone bitten by a snake who then looked at the copper snake lived.