Exodus 19:10 And the Lord said unto Moses, Go unto the people, and sanctify them to day and to morrow, and let them wash their clothes, 11 And be ready against the third day: for the third day the Lord will come down in the sight of all the people upon mount Sinai.
[Patriarchs & Prophets pp 304] The Lord said to Moses, “Go unto the people, and sanctify them today and tomorrow, and let them wash their clothes, and be ready against the third day: for the third day the Lord will come down in the sight of all the people upon Mount Sinai.” During these intervening days all were to occupy the time in solemn preparation to appear before God. Their person and their clothing must be freed from impurity. And as Moses should point out their sins, they were to devote themselves to humiliation, fasting, and prayer, that their hearts might be cleansed from iniquity.
The preparations were made, according to the command; and in obedience to a further injunction, Moses directed that a barrier be placed about the mount, that neither man nor beast might intrude upon the sacred precinct. If any ventured so much as to touch it, the penalty was instant death. On the morning of the third day, as the eyes of all the people were turned toward the mount, its summit was covered with a thick cloud, which grew more black and dense, sweeping downward until the entire mountain was wrapped in darkness and awful mystery. Then a sound as of a trumpet was heard, summoning the people to meet with God; and Moses led them forth to the base of the mountain.
From the thick darkness flashed vivid lightnings, while peals of thunder echoed and re-echoed among the surrounding heights. “And Mount Sinai was altogether on a smoke, because the Lord descended upon it in fire: and the smoke thereof ascended as the smoke of a furnace, and the whole mount quaked greatly.” “The glory of the Lord was like devouring fire on the top of the mount” in the sight of the assembled multitude. And “the voice of the trumpet sounded long, and waxed louder and louder.” So terrible were the tokens of Jehovah's presence that the hosts of Israel shook with fear, and fell upon their faces before the Lord. Even Moses exclaimed, “I exceedingly fear and quake.” Hebrews 12:21.
Exodus 19:17 And Moses brought forth the people out of the camp to meet with God; and they stood at the nether part of the mount. 18 And mount Sinai was altogether on a smoke, because the Lord descended upon it in fire: and the smoke thereof ascended as the smoke of a furnace, and the whole mount quaked greatly.
May The Lord add His blessing to the study of His word. God bless!