Numbers 21:6-9

21:6 So the Lord sent poisonous snakes among the people, and they bit the people; many people of Israel died. 21:7 Then the people came to Moses and said, “We have sinned, for we have spoken against the Lord and against you. Pray to the Lord that he would take away the snakes from us.” So Moses prayed for the people.

21:8 The Lord said to Moses, “Make a poisonous snake and set it on a pole. When anyone who is bitten looks at it, he will live.” 21:9 So Moses made a bronze snake and put it on a pole, so that if a snake had bitten someone, when he looked at the bronze snake he lived.