John Gills Exposition of the Bible Commentary - Exodus 19:15
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 from God himself: Aben Ezra has this note on the passage,"perhaps not a man slept that night, that he might hear the voice of the Lord... 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