John the Apostle
Revelation 16:5ESV·traditional attribution

And I heard the angel in charge of the waters say, “Just are you, O Holy One, who is and who was, for you brought these judgments.

Matthew Henry Presbyterian @wholebiblehenry

We had in the foregoing chapter the great and solemn preparation that was made for the pouring out of the vials; now we have the performance of that work. Here observe, I. That, though every thing was made ready before, yet nothing was to be put in execution without an immediate positive order from God; and this he gave out of the temple, answering the...

Commenting on Revelation 16:1-7

John Gill Reformed Baptist @doctorgill

For they have shed the blood of saints and prophets,.... Which shows that rivers and fountains cannot be literally understood, but men are designed, wicked and bloody men; and it is notorious to all, how much of the blood of the saints, of the preachers of the Gospel, of the prophets and witnesses, have been shed in Italy, Savoy, and other places near Rome, as...

Albert Barnes Presbyterian @notesbybarnes

Verse 5. And I heard the angel of the waters say. The angel who presides over the element of water; in allusion to the common opinion among the Hebrews that the angels presided over elements, and that each element was committed to the jurisdiction of a particular angel. Compare Barnes on "Re 7:1". Thou art righteous, O Lord.