In Exodus 20:18-20, we see Moses as the representative of the people: "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." The people feared to enter the presence of God, properly understanding that they were not worthy.
Moses's account continues (Exodus 20:21-24): "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."'" In these verses, we see the other side of the coin. Where in the first verses, God appointed Moses to mediate between Him and the people, here we see the negative side, His forbidding of any other mediator.
When Catholics or Eastern Orthodox pray to Mary or any of their other myriad of so-called "saints," they ask them to intercede for them with Jesus. They ask them to serve as mediators! The Catholic Answers website says, "Not only do those in heaven pray with us, they also pray for us." By whose appointment? Is it not by the appointment of men, in contravention of the commandment of God? Of course it is.