Carnac the Magnificent, an alter ego of Johnny Carson, once proclaimed the answer to the question in a sealed envelope to be "Sis boom bah." The question, revealed after his answer: "Describe the sound made when a sheep explodes."
Carnac may have had great powers of divination, but we mere mortals are less fortunate. Rarely can we predict the future to the degree we can answer even a single question before it's asked (exploding sheep optional). We make plans, we keep appointment books, and we do all sorts of things under the twin premises that tomorrow, next week, and next year will come and we can do something about them in advance. The future is rarely, if ever, so predictable, however. Plans are forced to change. Things are rescheduled. We just don't know what will happen next.
That leaves us in a perpetually tense position. We would all feel much better, much safer, much less anxious, if we could know with certainty what the future holds. God knows this, and so Jesus gives us a beautiful teaching in Matthew 6:25-34 that ends this way: "Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own" (v. 34). That's easier said than done, I know. But it's also easier to let go of worrying about tomorrow when you know God is already there handling things. And those of us who have read the back of the Book know one other thing: God wins. No matter what may happen before then, God will always win in the end.
That should make the future a little less tense.