Revelation 5:2

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

Revelation 5:5

And one of the elders said to me, Weep not; behold, the lion of the tribe of Judah, the root of David, has conquered, he is opening the book and its seven seals.

Revelation 18:21

And a mighty angel took up a stone like a great millstone, and cast it into the sea, saying, Thus with violence shall Babylon the great city be cast down, and shall be found no more.

Revelation 10:1

AND I saw another mighty angel come down from heaven, clothed with a cloud, and an iris was about his head, and his face was like the sun, and his feet like 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 elders said to me, Weep not; behold, the lion of the tribe of Judah, the root of David, has conquered, he is opening the book and its seven seals.