John is taking notes like a typical rabbinic or Greek student, an example of being studious, paying attention to what God is saying, and obeying Him through His most precious Word. This is also about how we are to glorify Him and not just seek what we want to get from Him. God’s judgment is at hand; the angel says there will be no more delays. If this does not strike fear in people, what will?  

• Raised his right hand was a way people at this time proclaimed an oath to vow allegiance in general or a specific task before their god. The book of Daniel also showed this; possibly, John is making the connection to Daniel, as Revelation is closely tied to it (Gen. 14:22-23; Deut 32:40; Dan. 12:7).

• Lives forever and ever refers to the eternal nature of God. As His faithful, we will also be preserved, as we will have a place in His marvelous eternity, heaven. This was also meant to encourage John’s readers who were going though persecutions and imminent martyrdom (Rev. 1:18; 4:9-10; 15:7).

• No more delay. This shows that the waiting is over and time has come. There will be no further postponement or interruption. The prayers of those in chapter six have been heard and God is at work (Dan. 12:7; Hab. 2:3; Mark 13:19; Rev. 2:21; 6: 9-11; 20:3).

• Mystery of God. The entirety of all that has been prophesied in the Old Testament has come or will come to its culmination by this time. All will be known; nothing will be hidden.