And the LORD said unto Moses, "Make thee a serpent and hang it up for a sign, and let as many as are bitten look upon it and they shall live." And Moses made a serpent of brass and set it up for a sign. And when the serpents had bitten any man, he went and beheld the serpent of brass and recovered.

Then they departed from mount Hor toward the reed sea: to compass the land of Edom. And the souls of the people fainted by the way. And the people spake against God and against Moses, "Wherefore hast thou brought us out of Egypt, for to die in the wilderness? For here is neither bread nor water, and our souls loatheth this light bread." Then the LORD sent fiery serpents among the people, which stung them: so that much people died in Israel.read more.
And the people came to Moses, and said, "We have sinned, for we have spoken against the LORD and against thee: make intercession to the LORD, that he take away the serpents from us." And Moses made intercession for the people.

He put away the hill altars, and brake the images and cut down the groves, and all to brake the brazen serpent that Moses made - for unto those days the children of Israel did burn sacrifice to it, and called it Nehushtan.

And as Moses lift up the serpent in the wilderness, even so must the son of man be lift up, that none that believeth in him perish: but have eternal life.