Exodus 19:9-11

New Century Version

⁹ And the Lord said to Moses, “I will come to you in a thick cloud and speak to you. The people will hear me speaking with you and will always trust you.” Then Moses told the Lord what the people had said.

¹⁰ The Lord said to Moses, “Go to the people and have them spend today and tomorrow preparing themselves. They must wash their clothes ¹¹ and be ready by the day after tomorrow. On that day I, the Lord, will come down on Mount Sinai, and all the people will see me.