The last book of the Bible is Revelation, it is a book of encouragement, comfort, and warning – about the end times.  From Jesus's instruction to the churches, to the great tribulation, to the return of Jesus and the church, to the 1000 year reign of Jesus, to the final defeat of Satan, to having a new heaven and a new earth.  God is just showing us that He has a plan.  By reading this book, you can know that God will take away His church to be with Him before the tribulation. So as believers, we have nothing to worry about – just go make disciples!