Exodus 20:18-26 ESV
Now when all the people saw the thunder and the flashes of lightning and the sound of the trumpet and the mountain smoking, the people were afraid and trembled, and they stood far off and said to Moses, “You speak to us, and we will listen; but do not let God speak to us, lest we die.” Moses said to the people, “Do not fear, for God has come to test you, that the fear of him may be before you, that you may not sin.” The people stood far off, while Moses drew near to the thick darkness where God was.
And the LORD said to Moses, “Thus you shall say to the people of Israel: ‘You have seen for yourselves that I have talked with you from heaven. You shall not make gods of silver to be with me, nor shall you make for yourselves gods of gold. An altar of earth you shall make for me and sacrifice on it your burnt offerings and your peace offerings, your sheep and your oxen. In every place where I cause my name to be remembered I will come to you and bless you. If you make me an altar of stone, you shall not build it of hewn stones, for if you wield your tool on it you profane it. And you shall not go up by steps to my altar, that your nakedness be not exposed on it.’
ESV: English Standard Version 2016