Exodus 20:24-26

“ ‘Make an altar of earth for me and sacrifice on it your burnt offerings and fellowship offerings, your sheep and goats and your cattle. Wherever I cause my name to be honored, I will come to you and bless you. If you make an altar of stones for me, do not build it with dressed stones, for you will defile it if you use a tool on it. And do not go up to my altar on steps, or your private parts may be exposed.’