Exodus 20:23

19 “Speak to us yourself and we will listen,” they said to Moses. “But do not let God speak to us, or we will die.”

20 “Do not be afraid,” Moses replied. “For God has come to test you, so that the fear of Him may be before you, to keep you from sinning.”

21 And the people stood at a distance as Moses approached the thick darkness where God was.

22 Then the LORD said to Moses, “This is what you are to tell the Israelites: ‘You have seen for yourselves that I have spoken to you from heaven.

23 You are not to make any gods alongside Me; you are not to make for yourselves gods of silver or gold.

24 You are to make for Me an altar of earth, and sacrifice on it your burnt offerings and peace offerings, your sheep and goats and cattle. In every place where I cause My name to be remembered, I will come to you and bless you.

25 Now if you make an altar of stones for Me, you must not build it with stones shaped by tools; for if you use a chisel on it, you will defile it.

26 And you must not go up to My altar on steps, lest your nakedness be exposed on it.’

Read all of Exodus 20