Revelation 5:2

And I saw mighty angel proclaiming with a loud voice, Who is worthy to open the book, and to break the seals thereon?

Revelation 5:5

And one of the presbyters said unto me, Weep not: behold the lion who is of the tribe of Judah, the root of David, hath prevailed, to open the book, and to break the seven seals upon it.

Revelation 18:21

And a mighty angel took up a stone as a great milestone, and cast it into the sea, saying, So with rapidity shall the great city Babylon be hurled into the deep, and never shall be found more.

Revelation 10:1

AND I saw another mighty angel descending from heaven, clothed with a cloud; and a rainbow on his head, and his countenance as the sun, and his feet as pillars of fire:

Treasury of Scripture Knowledge

Summary

And I saw a strong angel proclaiming with a loud voice, Who is worthy to open the book, and to loose the seals thereof?

Bible References

Who

Revelation 5:5
And one of the presbyters said unto me, Weep not: behold the lion who is of the tribe of Judah, the root of David, hath prevailed, to open the book, and to break the seven seals upon it.