Charles Ellicott Commentary Deuteronomy 5:23-27

"And it came to pass, when ye heard the voice out of the midst of the darkness, while the mountain was burning with fire, that ye came near unto me, even all the heads of your tribes, and your elders; and ye said, Behold, Jehovah our God hath showed us his glory and his greatness, and we have heard his voice out of the midst of the fire: we have seen this day that God doth speak with man, and he liveth. Now therefore why should we die? for this great fire will consume us: if we hear the voice of Jehovah our God any more, then we shall die. For who is there of all flesh, that hath heard the voice of the living God speaking out of the midst of the fire, as we have, and lived? Go thou near, and hear all that Jehovah our God shall say: and speak thou unto us all that Jehovah our God shall speak unto thee; and we will hear it, and do it." — Deuteronomy 5:23-27 (ASV)

The speech of the elders to Moses is more fully and exactly described here than in Exodus 20:0, where it is briefly summarized as expressing the mind of the whole people.

Why should we die? —The instinctive dread of death awakened by the Divine presence, and especially by the declaration of the Divine law, bears eloquent testimony to the truth that man was made to bear the Divine likeness, and to live a holy life.

For who is there of all flesh, that hath heard. —A famous passage in the Talmud makes all nations hear the words of the Law, every people in its own language. The thought is remarkable as bringing out a further analogy between the revelation at Sinai and the revelation on the Day of Pentecost, when every man heard in his own language the wonderful works of God.