Numbers 21:6-9

Then the LORD sent venomous snakes among them; they bit the people and many Israelites died. The people came to Moses and said, “We sinned when we spoke against the LORD and against you. Pray that the LORD will take the snakes away from us.” So Moses prayed for the people. The LORD said to Moses, “Make a snake and put it up on a pole; anyone who is bitten can look at it and live.” So Moses made a bronze snake and put it up on a pole. Then when anyone was bitten by a snake and looked at the bronze snake, they lived.