And he said to the people, “Be ready for the third day; do not go near a woman.”
Here, I. God intimates to Moses his purpose of coming down upon mount Sinai, in some visible appearance of his glory, in a thick cloud (Exo 19:9); for he said that he would dwell in the thick darkness (Ch2 6:1), and make this his pavilion (Psa 18:11), holding back the face of his throne when he set it upon mount Sinai, and spreading a cloud upon it, Job 26:9.
Commenting on Exodus 19:9-15
And he said unto the people, be ready against the third day,.... The third day from thence, the sixth of the month Sivan, against which day they were to prepare themselves, by washing their garments, and all other outward acts of sanctification and purity they were directed to, that they might be ready for the service of that day, to hear and receive the law...
And he said unto the people, Be ready against the third day: come not at [your] wives. (f) But give yourselves to prayer and abstinence, that you may at this time attend only upon the Lord, .