Exodus 20:4
> You shall not make for yourself a carved image, or any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in the water under the earth;
And
Numbers 21:8-9
>8 Then the Lord said to Moses, "Make a fiery serpent, and set it on a pole; and it shall be that everyone who is bitten, when he looks at it, shall live.9 So Moses made a bronze serpent, and put it on a pole; and so it was, if a serpent had bitten anyone, when he looked at the bronze serpent, he lived. So Moses made a bronze serpent, and put it on a pole; and so it was, if a serpent had bitten anyone, when he looked at the bronze serpent, he lived.
And finally
2 Kings 18:4
>4 He removed the high places and broke the sacred pillars, cut down the wooden image and broke in pieces the bronze serpent that Moses had made; for until those days the children of Israel burned incense to it, and called it Nehushtan.
So essentially, God gave Moses a commandment not to make any graven images, then a few years later told Moses to make a graven image that would heal people if the looked at it. A little while after that, the Children of Israel are worshipping that graven image, but God must have seen that coming. So what's going on here?