When the people heard the thunder and the trumpet blast and saw the lightning and the smoking mountain, they trembled with fear and stood a long way off. 1
References for Exodus 20:18
They said to Moses, "If you speak to us, we will listen; but we are afraid that if God speaks to us, we will die."
Moses replied, "Don't be afraid; God has only come to test you and make you keep on obeying him, so that you will not sin."
But the people continued to stand a long way off, and only Moses went near the dark cloud where God was.