John the Apostle
Revelation 16:10BSB·traditional attribution

And the fifth angel poured out his bowl on the throne of the beast, and its kingdom was plunged into darkness, and men began to gnaw their tongues in anguish

Matthew Henry Presbyterian @wholebiblehenry

In these verses we see the work going on in the appointed order. The fourth angel poured out his vial, and that fell upon the sun; that is, say some, upon some eminent prince of the popish communion, who should renounce their false religion a little while before his utter downfall; and some expect it will be the German emperor. And now what will be the consequence of this?

Commenting on Revelation 16:8-11

John Gill Reformed Baptist @doctorgill

And blasphemed the God of heaven,.... Who made it, and dwells in it, and from whence wrath is revealed, and comes upon the seat of the beast, upon the kingdom of antichrist, and the subjects of that kingdom; they will curse him who is of right their King, and their God, and look upwards to heaven, where he is, Isa 8:21 and this, because of...

Albert Barnes Presbyterian @notesbybarnes

Verse 10. And the fifth angel poured out his vial upon the seat of the beast. The previous judgments had been preparatory to this. They all had a bearing on this, and were all preliminary to it; but the "seat"-- the home; the centre of the power of the beasts had not yet been reached.