When I ponder God's justice and his mercy, I must ponder them in their separation and then in their unity. For justice and mercy appear at first to be but opposite ends of a spectrum, yet the Bible insists that God is both just and merciful, and he is the complete measure of both. This is what is meant by creative tension.
Creative tension is the act of holding two seemingly opposite ideas in your hands at the same time; it is the meshing together contentious ideas to see that they were designed to be together.
It is the recognization that God is both king and daddy, lord and saviour. As our king he is above us, beyond us, our master, and the one we pay homage to with our lives. Yet as our daddy, he draws close to us, instructs us, offers us care, and loves us unconditionally.
Yet somewhere at some point in time, we have watered down our theology and set aside our servanthood in favour of a God who simply loves us. We have set aside the Lordship of our Trinitarian God in favour of a feel-good story of sacrifice for us that lacks a reciprocal response. It is our responsibility (and it should be our desire) to look upon our God as our Lord and our Saviour. For He is not simply the one who loves us and saves us, but He is also the one who calls us to pick up our cross and follow Him. We are called to serve our risen Lord. Lordship demands following Him through the muck and the mire, in all situations, and not simply because He loves us.
Yet the comfort lies in Jesus as Saviour, not as Lord.
Similarly, creative tension is required for the ministry of the Church. This seeker-sensitive model of Church waters down the truth of the gospel in favour of an overemphasized love. Yes, love is unconditional, and the words 'overemphasized' and 'love' ought not to be beside one another, but truth is just as important and for far too long it has been compromised and set aside.
Liturgy, hard-to-swallow-sermons, the difficulty of the call to fishers of men, the impossibility of the sermon on the mount, these things have fallen to the wayside. It is so much easier to sing songs of happiness, to preach sermons of God's love, and to send forth the people to have a good week instead of actually calling them to change the world.
God has called us to be people of truth and love, not one, nor the other, but both. This is our call to creative tension.