John tells us in advance what will happen when the seventh angel blows its trumpet.
[The mighty angel] said, "There will be no more delay. When the seventh angel blows his trumpet, God's mysterious plan will be fulfilled. It will happen just as he announced it to his servants the prophets."
— Revelation 10:6-7 NLT (emphasis mine)
"God's mysterious plan will be fulfilled."
But what is God's plan?
And why does John call it mysterious?
The seventh trumpet
A little over a chapter later, the seventh angel blows his trumpet in Revelation 11:15. According to the mighty angel of chapter 10, the fulfilment of God's mysterious plan then occurs, but the information John gives us about what this is and what it looks like is very minimal at this stage of his letter.
And by "very minimal," I mean he gives us only five verses of detail. And one of those verses simply tells us that the twenty elders prostrate themselves on the ground to worship God. So, really, it's only four verses.
John has a habit of announcing things in advance. He does this throughout his messages to the seven assemblies, where he mentions things like the tree of life (2:7, see also 22:2, 14, 19), the second death (2:11, see also 20:6, 14; 21:8), the morning star (2:28, see also 22:16), the book of life (3:5, see also 13:8; 17:8; 20:12-15; 21:27), and the New Jerusalem (3:12, see also 21:2) but doesn't explain what he means by any of them until much later in his letter.
It's the same here. He gives us this tantalising taster, labels it as the fulfilment of God's mysterious plan, and leaves us wanting to know more. We're going to need to wait another nine chapters of his letter—and probably another nine or so articles—before we truly get to unpack what God's plan is.
However, Revelation 11 offers us some clues.
