Alcuin of York — on Rev 1:15 (COMMENTARY ON REVELATION)

“And his feet like unto fine brass, as in a burning furnace. The fabrication of fine brass is said to be as follows: copper is thrown into a furnace, a violent fire is applied to it, a certain medicine is also thrown into it all, and the copper as a result both gains a greater solidity and turns into the brightness of gold: whence it is appropriate for the feet like unto fine brass to refer to those last members of the Church that are to be melted by an intense fire of tribulation under the Antichrist, but will be found to be stronger and brighter after using the medicine of endurance. Because the trouble will be even more severe in Judea, where the Lord was crucified by the wicked Jews, another translation has "fine brass of Lebanon," which is said to be a mountain in Judea. And his voice as the voice of many waters. Above, he compared the voice of the one who appeared to a trumpet, and now he compares it to the voice of many waters, because what was first proclaimed by a few preachers, was afterwards proclaimed by the whole world. Alternatively, we could understand, by the voice of the trumpet, the voice of the Old and of the New Testament, and by the voice of many waters, love, whose law is manifold, as it is said in and thou shalt know that his law is manifold. [Cf. Job 11:6]”