In a word, the Future is, of all things, the thing least like eternity. It is the most completely temporal part of time—for the Past is frozen and no longer flows, and the Present is all lit up with eternal rays.... Hence nearly all vices are rooted in the future. Gratitude looks to the past and love to the present; fear, avarice, lust, and ambition look ahead.I think this is why I like Fr Caussade's teachings about the present moment -- because it helps me stay grounded in the one time where as Lewis says, freedom and actuality are offered to me.
I have noticed that the future can be a fearful thing for me -- that at times, my life in the present moment is constricted by fear of what MIGHT come. When it comes, however, it is not what I expected. Even if it is as bad as I expected, when it comes, it comes with something I can never have in future tense, only in present -- the strength, clearness and most of all, grace, to accept and deal with it. So the fear was fantastical, like those gibbering illusions in so many stories and movies that melt when they are confronted.
Another thing about the future -- it is inevitably telescoped, compressed. The present moment comes a tick at a time, every tick with its own ability and comprehension built into it. But when you imagine the future it is something like a landslide. If I'm afraid to clean behind the toilet (and often I am VERY afraid!) I picture a whole collage of moments, basically both compressed and stretching out into infinity, and it seems unbearable. But when I go to actually do it, it's one moment at a time, and no one moment is unendurable. Even the most uncomfortable moments go by one after the other.
I think this is why Jesus so often warns against always waiting for the end times, or "worrying about tomorrow" because he knows our imaginations can picture such great magnitude, whereas our actual existence is always filtered like the sand through the middle of the hourglass.
We are to prepare for the future, for this is our present duty, but our preparation takes place in the light of eternity, not the future, so our job is to keep oil in our lamps, like the wise virgins, not incinerate it in a great burst or spill it in our fear or let it dry out because we're thinking about trivia that is out of our control.