John the Apostle
Revelation 13:7ESV·traditional attribution

Also it was allowed to make war on the saints and to conquer them. And authority was given it over every tribe and people and language and nation,

Matthew Henry Presbyterian @wholebiblehenry

We have here an account of the rise, figure, and progress of the first beast; and observe, 1. From what situation the apostle saw this monster. He seemed to himself to stand upon the sea-shore, though it is probable he was still in a rapture; but he took himself to be in the island Patmos, but whether in the body or out of the body he could not tell. 2.

Commenting on Revelation 13:1-10

John Gill Reformed Baptist @doctorgill

And it was given unto him to make war with the saints,.... The remnant of the woman's seed, Rev 12:17, whom God has set apart for himself, Christ has cleansed from sin by his blood, and the Holy Spirit has sanctified by his grace; and who under the influence of it live holy lives and conversations; against such Satan always bore an enmity; and it...

Albert Barnes Presbyterian @notesbybarnes

Verse 7. And it was given unto him. By the same power that taught him to blaspheme God and his church. . To make war with the saints. See this fully illustrated in , and at the end of that chapter. And to overcome them. In those wars.