Numbers 21:7-9

7The people then came to Moses and said, “We have sinned by speaking against the Lord and against you. Intercede with the Lord so that he will take the snakes away from us.” And Moses interceded for the people.

8Then the Lord said to Moses, “Make a snake image and mount it on a pole. When anyone who is bitten looks at it, he will recover.”

9So Moses made a bronze snake and mounted it on a pole. Whenever someone was bitten, and he looked at the bronze snake, he recovered.