Why weren't the Israelites destroyed when God's presence came down on Mount Sinai?
The Israelites survived because God had set them apart as His covenant people. Though His presence descended on Mount Sinai with fire and smoke, and Israel stood at the foot of the mountain, they were not destroyed; this unique event demonstrated they were a special, set-aside people.
Les explains that Moses is recalling Mount Sinai, where God came down on the mountain, the mountain was on fire, and smoke pillared while Israel stood at the foot. They weren't destroyed even though the presence of God was that close. God asks whether any people ever heard His voice speaking out of the midst of the fire and lived, and the answer is never. Israel is therefore a covenant, special set-aside people.
For ask now of the days that are past, which were before thee, since the day that God created man upon the earth, and ask from the one side of heaven unto the other, whether there hath been any such thing as this great thing is, or hath been heard like it?
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