Daniel was told to shut up the vision, and to also seal the book:

Daniel 8:26 And the vision of the evening and the morning which was told is true: wherefore shut thou up the vision; for it shall be for many days.

Daniel 12:4 But thou, O Daniel, shut up the words, and seal the book, even to the time of the end: many shall run to and fro, and knowledge shall be increased.

  9 And he said, Go thy way, Daniel: for the words are closed up and sealed till the time of the end.

John was told to seal up the things which the seven thunders uttered:

Revelation 10:4 And when the seven thunders had uttered their voices, I was about to write: and I heard a voice from heaven saying unto me, Seal up those things which the seven thunders uttered, and write them not.

A similar thing was said to Isaiah, to seal the law:

Isaiah 8:16 Bind up the testimony, seal the law among my disciples.

Also, "as the words of a book that is sealed,":

Isaiah 29:11 And the vision of all is become unto you as the words of a book that is sealed, which men deliver to one that is learned, saying, Read this, I pray thee: and he saith, I cannot; for it is sealed:

So, back in Daniel 12:4, which book was he to seal, "O Daniel, shut up the words, and seal the book"?

Is it the Bible?  or is it restricted to the sealing of the book of Daniel?

The book is to be sealed till the time of the end.

When, at the time of the end, is it to be unsealed?  before the tribulation?  during the tribulation?  at Jesus' return?  during the kingdom?

If it is not the same as the book being unsealed in Revelation 4, then do any scriptures describe it being unsealed?

If it is not unsealed by Jesus, then who unseals it?

Or, is the unsealing, to be understood as some kind of generalized unsealing, corporately amongst believers?

At the end of what John saw and heard, he was told to not seal the book:

Revelation 22:10 And he saith unto me, Seal not the sayings of the prophecy of this book: for the time is at hand.

Which book?  the Bible?  or is this restricted to not sealing the book of Revelation?

If it is referring to not sealing the book of Revelation, and there has been such difference of understandings regarding that book;

Then if the book of Daniel was to be sealed, then how much more differences, or even misunderstandings, are there, regarding the book of Daniel?

If it hasn't been unsealed, yet?  or has it been?

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