Exodus 3:1-6 (NASB95)
1 Now Moses was pasturing the flock of Jethro his father-in-law, the priest of Midian; and he led the flock to the west side of the wilderness and came to Horeb, the mountain of God.
2 The angel of the Lord appeared to him in a blazing fire from the midst of a bush; and he looked, and behold, the bush was burning with fire, yet the bush was not consumed.
3 So Moses said, “I must turn aside now and see this marvelous sight, why the bush is not burned up.”
4 When the Lord saw that he turned aside to look, God called to him from the midst of the bush and said, “Moses, Moses!” And he said, “Here I am.”
5 Then He said, “Do not come near here; remove your sandals from your feet, for the place on which you are standing is holy ground.”
6 He said also, “I am the God of your father, the God of Abraham, the God of Isaac, and the God of Jacob.” Then Moses hid his face, for he was afraid to look at God.

Exodus 19:1-6 (NASB95)
1 In the third month after the sons of Israel had gone out of the land of Egypt, on that very day they came into the wilderness of Sinai.
2 When they set out from Rephidim, they came to the wilderness of Sinai and camped in the wilderness; and there Israel camped in front of the mountain.
3 Moses went up to God, and the Lord called to him from the mountain, saying, “Thus you shall say to the house of Jacob and tell the sons of Israel:
4 ‘You yourselves have seen what I did to the Egyptians, and how I bore you on eagles’ wings, and brought you to Myself.
5 ‘Now then, if you will indeed obey My voice and keep My covenant, then you shall be My own possession among all the peoples, for all the earth is Mine;
6 and you shall be to Me a kingdom of priests and a holy nation.’ These are the words that you shall speak to the sons of Israel.”

Deuteronomy 4:10-15 (NASB95)
10 “Remember the day you stood before the Lord your God at Horeb, when the Lord said to me, ‘Assemble the people to Me, that I may let them hear My words so they may learn to fear Me all the days they live on the earth, and that they may teach their children.’
11 “You came near and stood at the foot of the mountain, and the mountain burned with fire to the very heart of the heavens: darkness, cloud and thick gloom.
12 “Then the Lord spoke to you from the midst of the fire; you heard the sound of words, but you saw no form—only a voice.
13 “So He declared to you His covenant which He commanded you to perform, that is, the Ten Commandments; and He wrote them on two tablets of stone.
14 “The Lord commanded me at that time to teach you statutes and judgments, that you might perform them in the land where you are going over to possess it.
15 “So watch yourselves carefully, since you did not see any form on the day the Lord spoke to you at Horeb from the midst of the fire,

Exodus 33:18-23 (NASB95)
18 Then Moses said, “I pray You, show me Your glory!”
19 And He said, “I Myself will make all My goodness pass before you, and will proclaim the name of the Lord before you; and I will be gracious to whom I will be gracious, and will show compassion on whom I will show compassion.”
20 But He said, “You cannot see My face, for no man can see Me and live!”
21 Then the Lord said, “Behold, there is a place by Me, and you shall stand there on the rock;
22 and it will come about, while My glory is passing by, that I will put you in the cleft of the rock and cover you with My hand until I have passed by.
23 “Then I will take My hand away and you shall see My back, but My face shall not be seen.”