From the Crossway blog:
Guest post from Jim Hamilton, Part 1
Do you want to ponder a question that has roots that stretch so far back into eternity past that we will never come to the end of them? How about this: What is God’s ultimate purpose? I would argue that God’s ultimate purpose is to display his glory and that his glory is seen most clearly when people understand and feel the way that God’s justice highlights mercy (cf. Rom 9:22-23). We have to feel the weight of God’s almighty, everlasting, righteous wrath crushing us so that we will perceive the liberating relief of God’s mercy. When people understand the gospel, they perceive the glory of God’s justice and his mercy in Christ by the power of the Holy Spirit.
I contend that every single biblical author had God’s glory in salvation through judgment at the heart of his theology. If I am right about this, then the biblical authors have communicated what God’s ultimate purpose is, and the biblical authors are in agreement with each other.