The thunders and lightnings were sent partly as evidences and tokens both of God's glorious presence, and of the anger of God, and the dreadful punishments due to the transgressors of the law now to be delivered; and partly as means to humble, and awaken, and convince, and terrify proud and secure sinners, that they might more reverently attend to the words and commands of God, more willingly yield obedience to them, and be more afraid of the violation of them. A thick cloud was both a fit mean for the production and reception of the thunders and lightnings, and a signification as well of the invisible and unconceivable nature of God, as of the obscurity of the legal dispensation in regard of its types and shadows, & c., 2 Corinthians 3:13,18 2 Corinthians 4:6. The trumpet was a fit instrument, both for the promulgation of God's law, and for the signification of that war that is between God and sinners. All the people, Moses himself not excepted, as appears from Hebrews 12:21.
Related Commentaries of Exodus 19:16
Exodus 19:16
16 And it came to pass on the third day in the morning, that there were thunders and lightnings, and a thick cloud upon the mount, and the voice of the trumpet exceeding loud; so that all the people that was in the camp trembled.