As you may know, I was a doctoral student at the University of Basel from 1980-1983. At Basel, once your dissertation has been approved by the faculty, you must wait 6 months before taking your oral exam. (Orals in Basel, unlike here, occur after you write your dissertation, not before.) The day of the exam finally arrived and I sat before my persecutors questioners with fear and trepidation. I think I did fairly well, but on one question I was completely stumped. "What theological concept holds that Christians are actively taking part in the kingdom of God, although that kingdom will not reach its full expression until sometime in the future? Specifically, what two expressions do theologians use to describe this tension between the ___________ and the __________?"
Now, I did indeed know the answer, but for the life of me I couldn't think clearly enough to utter the simple words, "Schon, noch nicht." Is there a biblical basis for this "Already, not yet" concept? You bet there is. The problem comes when we become unbalanced in our theology. Overemphasize the "now kingdom" and you will take yourself too seriously. The kingdom decays into utopianism, theocracy, or the social gospel. On the other, overemphasize the "coming kingdom" and you run the risk of being "so heavenly minded you're no earthly good."
Balance between the already and the not yet of the kingdom remains essential for our spiritual and psychological health as believers. The now kingdom and the coming kingdom can never be separated. Boldness for down-to-earth ministry is best nourished by clear-thinking expectation of a kingdom to come.