The Mighty Angel stands in his place and speaks. The speech is described as the roar of a lion, and he is answered by the “seven thunders.” This description is significant for several reasons. It is the only place in Revelation where an angelic messenger speaks, but the words are not recorded. Why is the shout described in this way, and not recorded?
3 Baruch 11:4 And while we were waiting, there was a noise from the highest heaven like triple thunder. And I Baruch said, “Lord, what is this noise?” And he said to me, “Michael is descending to accept the prayers of men.”
So he spoke in prayer, and Zeus the counsellor heard him. Straightway he thundered from gleaming Olympus, from on high from out the clouds; and goodly Odysseus was glad. (The Odyssey, 20.100-104).
Why are there “seven thunders?” Psalm 29:3-9 has a seven fold description of the voice of God as thunder (although the word “voice” is not repeated seven times.) There is a rabbinic tradition that the voice of God was heard as seen thunders on Mt. Sinai (Exod. Rab. 28:6).
As John prepared to write the content of the words spoken by the thunders, a “voice from heaven” prevents him. John is told to “seal up the vision” and not write it down. The source of the voice is not identified and it is common in Revelation for John to hear an unidentified voice from heaven. Given the background texts where a divine voice sounds like thunder, perhaps this is the voice of God prohibiting John from writing what the thunders said.
The way the command is given is odd: he is told to seal up the vision (which would imply keeping it a secret), but also not to write anything down. If he had not written the words, what is the point of also sealing the scroll? There is a tradition in Jewish apocalyptic of a person being given revelation but forbidden to share it. David Aune suggested this ensures that prophet alone knows the information, making him “wiser” than his readers. It was a mark of authenticity to hold back a little revelation from the readers, if you gave it all then perhaps there were skeptics.
So what did the seven thunders say? Obviously we cannot know since it is still a secret, but John may have been given another series of judgments like the seals, trumpets, and bowls. He was told not to record this series for some reason. Caird suggested the reason John is told not to record the content of the visions is that God “cancelled” the judgments out of his grace and mercy (Revelation, 126-127). This would mean there were four sets of seven judgments, one set was set aside, perhaps an allusion to the four sets of curses in Leviticus 26:14-46.