Hebrews 12:20

For they could not endure that which was commanded
In the law; not that they disliked and despised the law, as unregenerate men do; but they could not endure it, or bear it, as a yoke, it being a yoke of bondage; nor as a covenant of works, it requiring perfect obedience, but giving no strength to perform; and as it showed them their sins, but did not direct them to a Saviour; as it was an accusing, cursing, and condemning law; and, as a fiery one, revealing wrath, and filling the conscience with it; unless this should have any respect to the following edict, more particularly:

and if so much as a beast touch the mountain, it shall be stoned or
thrust through with a dart;
and, if a beast, much more a man: and, how easily, through inadvertence, might this be done? and how terrible was the punishment? nothing less than death, by stoning, or being shot: and this they could not bear to hear, or think of: the last clause, "or thrust through with a dart", is wanting in the Alexandrian and Beza's Claromontane copies, in the Vulgate Latin, and all the Oriental versions; and yet is necessary to be retained, being in the original text, in ( Exodus 19:12 Exodus 19:13 ) .