Rev 22:8

Rev 22:6 was the beginning of the Angels close out of this vision to John. You can go back to the 1st chapter and read again Rev 1:3 " Blessed is he who reads and those who hear the words of the prophecy, and heed the things which are written in it; for the time is near. We've seen the Lord saying He will return without necessary delay (without necessary delay, is coming through in the original Greek texts, prime example of the original languages) there are necessary delays. God has also pointed out the He is not slow as some count slow. It's His plan, He is sovereign and it will come to pass. This prophecy (The Book of Revelation) explains the things that must come to pass before Christ's return. Hebrews 10:23 "Let us hold fast the confession of our hope without wavering, for He who promised is faithful" and then to Hebrews 10:25 "Not forsaking our own assembling together, as is the habit of some, but encouraging one another; and all the more as you see the day drawing near." To those in disbelief, all I can say is give Christ another hearing, time is passing - once in the eternal state your free chance is gone. The punishment for sin is death, Christ paid that price, in your place on a cross and on the third day He was raised again. In your simple belief and acceptance of that, gives you immediate access to an everlasting life; as opposed to everlasting life in the Lake of Fire with Satan and his fallen angels. The worst part of that would be knowing eternally, how easy it would have been, not to be there.