Revelation 15:1: And I saw ... seven angels having the seven last plagues; for in them is filled up the wrath of God.

When John saw the Grand Sign of the Son of Man in Revelation 15:1,¹ he separately saw seven angels having the seven last plagues.² The seven angels are not the Grand Sign. They also differ from the seven angels that John saw in Revelation chapter 14, who fly through the midst of heaven to carry out their duties immediately before the Grand Sign appears in heaven.³ The seven angels in Revelation 15:1 have the seven last plagues called Vial Plagues.⁴ These last seven Vial Plagues are collectively the Third Woe of the seventh seal and they begin when the seventh trumpet angel sounds his symbolic trump.⁵

The timing and function of these last seven angels differs from the seven trumpet angels introduced in Revelation chapter 8.⁶ When the last seven angels pour out their Vial Plagues in rapid succession⁷ this will complete the millennial cleansing of the earth before the Second Coming.⁸ They are seven in number to signify God's perfect judgments against the wicked during the Third Woe.⁹

Revelation chapter 16 identifies the seven last plagues as seven vials,¹⁰ and for this reason they are called Vial Plagues. In these last seven Vial Plagues is filled up¹¹ the wrath of God.¹² John uses the present verb tense in Revelation 15:1 to convey the idea that the seven Vial Plagues are so certain to occur in the future it's like they had already occurred at the time of John's vision in 96 AD.¹³

The seven angels of the Third Woe will receive their seven vials filled with God's wrath in Revelation 15:7.¹⁴ They will then pour out the seven Vial Plagues on earth in Revelation chapter 16, after the Grand Sign of the Son of Man is given in Revelation 15:1.¹⁵