Exodus 19:18-20 New King James Version (NKJV)

¹⁸ Now Mount Sinai was completely in smoke, because the Lord descended upon it in fire. Its smoke ascended like the smoke of a furnace, and the whole mountain^[a] quaked greatly. ¹⁹ And when the blast of the trumpet sounded long and became louder and louder, Moses spoke, and God answered him by voice. ²⁰ Then the Lord came down upon Mount Sinai, on the top of the mountain. And the Lord called Moses to the top of the mountain, and Moses went up.