Albert Barnes Commentary Revelation 10:8

"And the voice which I heard from heaven, [I heard it] again speaking with me, and saying, Go, take the book which is open in the hand of the angel that standeth upon the sea and upon the earth." — Revelation 10:8 (ASV)

And the voice which I heard from heaven (Revelation 10:4). This is not the voice of the angel, but a direct divine command.

Said, Go and take the little book that is open, etc. That is, take it out of his hand, and do with it as you will be commanded.

There is a very strong resemblance between this passage and the account contained in Ezekiel 2:9-10; 3:1-3. Ezekiel was directed to go to the house of Israel and deliver a divine message, whether they would hear or forbear; and so that he might understand what message to deliver, he was shown a roll of a book, written within and without.

That roll he was commanded to eat, and he found it to be in his mouth as honey for sweetness. John has added to this the circumstance that, though sweet in the mouth, it made the belly bitter.

The additional command (Revelation 10:11), that he must yet prophesy before many people, leads us to suppose that he had the narrative in Ezekiel in mind. For, as the result of his eating the roll, he was commanded to go and prophesy to the people of Israel.

The passage here (Revelation 10:8) introduces a new symbol, that of “eating the book,” and evidently refers to something that was to occur before the mystery should be finished; that is, before the seventh trumpet should sound.

Which is open in the hand, etc. Regarding the symbolical meaning of the word “open,” as applied to the book, see the comments on Revelation 10:2.