Exodus 19:18
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.
And Mount Sinai was altogether on a smoke,.... Not from nature, as volcanos, but for a reason after given; it seemed to be one large body of smoke, nothing else to be seen but smoke; an emblem of the darkness of the legal dispensation, which was full of obscure types and figures, of dark shadows and smoky sacrifices, to which the clear day, of the Gospel dispensation is opposed, see 2 Corinthians 3:12
because the LORD descended upon it in fire; in flaming fire, as the Targums, which set the mountain on fire, and caused this prodigious smoke; for if he, who is a consuming fire, but toucheth the hills and mountains, they smoke, Ps 104:32
and the smoke thereof ascended as the smoke of a furnace such an one as that which Abraham in vision saw, Genesis 15:17
and the whole mount quaked greatly; to which circumstance Deborah refers in her song, when she speaks of mountains melting and flowing from before the presence of the God of Israel, and particularly of Sinai, Judges 5:4, and the psalmist, who makes mention of the earth shaking, and the heavens dropping, and of Sinai being moved at his presence, Psalms 68:8, it is probable there was an earthquake at this time, which sometimes attends thunders and lightnings, see