That's a question that still puzzles me, but I believe the answer is twofold. Faith is the assurance of things hoped for. I. That's faith, but I believe that's faith in process, in time, not in God. This is a tried and true kind of faith in life itself. We've seen it all happen in our lives before.
Bad times come and bad times go.
If we have faith in time, distance, and our ability to survive hardship, we are rewarded by life returning to balance. This is a necessary faith in the human animal. Without it we give up hope, we give up our lives and our free will to guide our own lives and make our own decisions about how we'll deal with the trials that inevitably come. Faith as the assurance of things hoped for is that faith in the strength deep inside of us, the part of God within all of us, that keeps us alive and hoping for better things. This is the faith in ourselves that motivates us to go on day to day, to keep breathing and trying and striving.