18 and mount Sinai [is] wholly a smoke from the presence of Jehovah, who hath come down on it in fire, and its smoke goeth up as smoke of the furnace, and the whole mount trembleth exceedingly;
18
Mount Sinai was covered with smoke, because the LORD descended on it in fire. The smoke billowed up from it like smoke from a furnace, and the whole mountain trembled violently.
Young's Literal Translation is in the public domain.