Hebrews 12:18-24
“For you are not come unto a fire that might be touched and that burned, and unto blackness, and darkness, and tempest, and the sound of a trumpet, and the voice of words, which voice they that heard entreated that the word should not be spoken to them any more. (For they could not endure that which was commanded, And if so much as a beast touch the mountain, it shall be stoned. And so terrible was the sight, that Moses said, I exceedingly fear and quake.) But you have come unto Mount Sion, and unto the city of the living God, the Heavenly Jerusalem; and to an innumerable company of Angels, to the general assembly, and Church of the first-born which are written in Heaven; and to God the Judge of all; and to the spirits of just men made perfect: and to Jesus the Mediator of the New Covenant: and to the blood of sprinkling that speaks better things than that of Abel.”
1. Wonderful indeed were the things in the Temple, the Holy of Holies; and again awful were those things also that were done at Mount Sina, “the fire, the darkness, the blackness, the tempest.” For, it says, “God appeared in Sina,” and long ago were these things celebrated. The New Covenant, however, was not given with any of these things, but has been given in simple discourse by God.
See then how he makes the comparison in these points also. And with good reason has he put them afterwards. For when he had persuaded them by innumerable [arguments], when he had also shown the difference between each covenant, then afterwards, the one having been already condemned, he easily enters on these points also.
And what says he? “For you are not come unto a fire that might be touched, and that burned, and unto blackness, and darkness, and tempest, and the sound of a trumpet, and the voice of words; which they that heard entreated that the word should not be spoken to them any more.”
These things, he means, are terrible; and so terrible that they could not even bear to hear them, that not even “a beast” dared to go up. (But things that come hereafter are not such. For what is Sina to Heaven? And what the “fire which might be touched” to God who cannot be touched? For “God is a consuming fire.”) For it is said, “Let not God speak, but let Moses speak unto us. And so fearful was that which was commanded, Though even a beast touch the mountain, it shall be stoned; Moses said, I exceedingly fear and quake.” What wonder as respects the people? He himself who entered into “the darkness where God was,” says, “I exceedingly fear and quake.”
2. “But you have come unto Mount Sion and unto the city of the living God, the heavenly Jerusalem: and to an innumerable company of angels and to the general assembly and Church of the first-born which are written in Heaven, and to God the Judge of all, and to the spirits of just men made perfect, and to Jesus the Mediator of the New Covenant, and to the blood of sprinkling, that speaks better [things] than that of Abel.”
Instead of “Moses,” Jesus. Instead of the people, “myriads of angels.”
Of what “first-born” does he speak? Of the faithful.
“And to the spirits of just men made perfect.” With these shall you be, he says.
“And to Jesus the mediator of the New Covenant, and to the blood of sprinkling that speaks better [things] than that of Abel.” Did then the [blood] “of Abel” speak? “Yea,” he says, “and by it he being dead yet speaks.” And again God says, “The voice of your brother's blood cries unto Me.” Either this [meaning] or that; because it is still even now celebrated: but not in such way as that of Christ. For this has cleansed all men, and sends forth a voice more clear and more distinct, in proportion as it has greater testimony, namely that by facts.
Source: Homilies on the Epistle to the Hebrews (New Advent)