Exodus 20:18-26

And all the people perceived the thunderings, and the lightnings, and the voice of the trumpet, and the mountain smoking: and when the people saw it, they trembled, and stood afar off. And they said unto Moses, Speak thou with us, and we will hear; but let not God speak with us, lest we die. And Moses said unto the people, Fear not: for God is come to prove you, and that his fear may be before you, that ye sin not. And the people stood afar off, and Moses drew near unto the thick darkness where God was. And Jehovah said unto Moses, Thus thou shalt say unto the children of Israel, Ye yourselves have seen that I have talked with you from heaven. Ye shall not make other gods with me; gods of silver, or gods of gold, ye shall not make unto you. An altar of earth thou shalt make unto me, and shalt sacrifice thereon thy burnt-offerings, and thy peace-offerings, thy sheep, and thine oxen: in every place where I record my name I will come unto thee and I will bless thee. And if thou make me an altar of stone, thou shalt not build it of hewn stones; for if thou lift up thy tool upon it, thou hast polluted it. Neither shalt thou go up by steps unto mine altar, that thy nakedness be not uncovered thereon.