Exodus 19:8

Now therefore, if you will indeed obey my voice and keep my covenant, then you shall be my own possession from among all peoples; for all the earth is mine;

and you shall be to me a kingdom of priests and a holy nation.’ These are the words which you shall speak to the children of Israel.”

Moses came and called for the elders of the people, and set before them all these words which the LORD commanded him.

The LORD said to Moses, “Behold, I come to you in a thick cloud, that the people may hear when I speak with you, and may also believe you forever.” Moses told the words of the people to the LORD.

The LORD said to Moses, “Go to the people, and sanctify them today and tomorrow, and let them wash their garments,

and be ready for the third day; for on the third day the LORD will come down in the sight of all the people on Mount Sinai.