We learn in these verses that a seismic change is coming. The entire physical world as we know it will be consumed by fire and a new heavens and new earth will appear. This physical change will come with a moral change as the values of this world are swept away, replaced by a kingdom of righteousness.
This change has profound consequences for how we should be living today. By the power of the Spirit, we are called to live holy lives and to hasten the coming of Christ.