John Gills Exposition of the Bible Commentary - Exodus 19:10
And the Lord said unto Moses ,.... On the fourth day, according to the Targum of Jonathan: go unto the people ; go down from the mountain, from the top of it, where he now was, to the camp of Israel, which was pitched before it: and sanctify them today and tomorrow ; the fourth and fifth days of the month; that is, he was, to instruct them how they were to sanctify themselves in an external way, by washing themselves, as after mentioned, their bodies and clothes, and by abstaining... read more
Matthew Henry's Complete Commentary - Exodus 19:9-15
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 (Exod. 19:9); for he said that he would dwell in the thick darkness (2 Chron. 6:1), and make this his pavilion (Ps. 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. This thick cloud was to prohibit curious enquiries into things secret, and to command an awful adoration of that which was... read more