It is important to realise that God shows John the Apostle a vision which is not sequential in time. God’s way of looking at events, is not sequential, because He sees the end from the beginning and visa-versa. We humans tend to think in a sequential flow of time, but God, the eternally existent One, by His very nature, transcends all time and space.
Chapter 15 of the Book of Revelation records a vision that gives the reader an introduction to the 7 vials of wrath being poured out on the earth. These are the final phase of the wrath of God. Jesus Christ shows John a vision of the believers who are saved and in heaven yet also of the coming 7 vials to be poured out by angels. This does not means the saved avoid living through the period of this final wrath of God.