Exodus 19:9-11

New Revised Standard Version, Anglicised Catholic Edition

⁹ Then the Lord said to Moses, ‘I am going to come to you in a dense cloud, in order that the people may hear when I speak with you and so trust you ever after.’

The People Consecrated

When Moses had told the words of the people to the Lord, ¹⁰ the Lord said to Moses: ‘Go to the people and consecrate them today and tomorrow. Have them wash their clothes ¹¹ and prepare for the third day, because on the third day the Lord will come down upon Mount Sinai in the sight of all the people.