And the LORD said to Moses, "Say this to the people of Israel: You are witnesses that I have spoken to you from heaven.
Remember, you must not make or worship idols of silver or gold."
"The altars you make for me must be simple altars of earth. Offer on such altars your sacrifices to me -- your burnt offerings and peace offerings, your sheep and goats and your cattle. Build altars in the places where I remind you who I am, and I will come and bless you there.
If you build altars from stone, use only uncut stones. Do not chip or shape the stones with a tool, for that would make them unfit for holy use.
And you may not approach my altar by steps. If you do, someone might look up under the skirts of your clothing and see your nakedness."