From this essential difference in the nature of the revelations a twofold contrast is apparent in the phenomena of Sinai and Zion. Sinai revealed the terrible side of God's character, Zion the peaceful tenderness of His love. The revelation on Sinai was earthly; that on Zion is spiritual.
There can be no question that the Apostle intends to contrast the terrible appearances on Sinai with the calm serenity of Zion. The very rhythm of his language expresses it. But the key to his description of the one and the other is to be found in the distinction already mentioned. On Sinai the unappeased wrath of God is revealed. Sacrifices are instituted, which, however, when established, evoke no response from the offended majesty of Heaven. Of the holiest place of the old covenant the best thing we can say is that the lightning and thunders of Sinai slumbered therein. The author's beautiful description of the sunny steep of Zion is framed, on the other hand, in accordance with his frequent and emphatic declaration that Christ has entered the true holiest place, having obtained for us eternal redemption. All that the Apostle says concerning Sinai and Zion gathers around the two conceptions of sin and forgiveness.
The Lord spake on Sinai out of the midst of the palpable, enkindled fire, of the cloud, and of the thick darkness, with a great voice. All the people heard the voice. They saw "that God doth talk with man, and he liveth." They begin to hope. But immediately they bethink them that, if they hear the voice of the Lord any more, they will die. Thus does a guilty conscience contradict itself! Again, the people are invited to come up into the mount when the trumpet shall sound long. Yet, when the voice of the trumpet sounds long and waxes louder and louder, they are charged not to come up unto the Lord, lest He break forth upon them. All this appearance of inconsistency is intended to symbolize that the people's desire to come to God struggled in vain against their sense of guilt, and that God's purpose of revealing Himself to them was contending in vain with the hindrances that arose from their sins. The whole assembly heard the voice of the Lord proclaiming the Ten Commandments. Conscience-smitten, they could not endure to hear more. They gat them into their tents, and Moses alone stood on the mountain with God, to receive at His mouth all the statutes and judgments which they should do and observe in the land which He would give them to possess. The Apostle singles out for remark the command that, if a beast touched the mountain, it should be stoned to death. The people, he says, could not endure this command. Why not this? It connected the terrors of Sinai with man's guilt. According to the Old Testament idea of Divine retribution, the beasts of the earth fall under the curse due to man. When God saw that the wickedness of man was great in the days of Noah, He said, "I will destroy both man and beast."[367] When, again, He blessed Noah after the waters were dried up, He said, "I, behold, I establish My covenant with you and with every living creature that is with you."[368] Similarly, the command to put to death any beast that might haply touch the mountain revealed to the people that God was dealing with them as sinners. Moses himself, the mediator of the covenant, who aspired to behold the glory of God, feared exceedingly. But his fear came upon him when he looked and beheld that the people had sinned against the Lord their God[369] and made them a molten calf. His fear was not the prostration of nervous terror. Remembering, when he had descended, the awful sights and sounds witnessed on the mountain, he was afraid of the anger and hot displeasure of God against the people, who had done wickedly in the sight of the Lord. Almost every word the Apostle has here written bears closely upon the moral relation between a guilty people and the angry God.