If we truly believe in God. If we truly believe God is the author of all things (without sinking into a belief in predestination). If we truly have faith in His presence. If we truly want to listen to Him and follow Him. Then, why do we worry?
Far too many among us spend our days and nights wringing our hands about yesterday and tomorrow. We think about what went wrong in an earlier time. And we fixate on what's coming next. We do these things in part because no one has taught us or encouraged us to live in the 'eternal now' of God.
If we did do that, then we surely wouldn't experience the rampant anxiety (and every other form of dis-ease) that pervades our society. We would in fact become more and more peaceful by the day.
Even more than that, if we truly live our lives with complete faith in God, then we would grow ever closer to Him in this life. After all, union with God for all eternity is the singular goal for all of us.