The people complained about the lack of food and water during the Exodus, so God sent fiery serpents to bite them.
Make a brass serpent, put it on a pole, and tell the bite victims to look at it
When many died from the bites, Moses asked God to take away the serpents.
And Moses made a serpent of brass, and put it upon a pole, and it came to pass, that if a serpent had bitten any man,
when he beheld the serpent of brass, he lived.
Numbers 21:8And the LORD said unto Moses, Make thee a fiery serpent, and set it upon a pole: and it shall come to pass, that every one that is bitten,
when he looketh upon it, shall live.
And Moses made a serpent of brass, and put it upon a pole, and it came to pass, that if a serpent had bitten any man,
when he beheld the serpent of brass, he lived.
Numbers 21:8