This passage in the Bible is often taken to mean that we should not worry about where our meals will come from and how we will earn our money. The Creator will provide. Birds and flowers don't hoard, nor do they stress about clothing, for all unfolds in its own time.
As I contemplated what I was supposed to DO next in my life, in my career (something I obsess about and have done so ad nauseum for years), this passage came to me. I realized it was about more than just don't stress about money.
It is also about not focusing on our external structures, but instead bringing our attention to the connection with Spirit within us. Not getting wrapped up in our egos and it's rules, but bringing ourselves centered into our eye of the heart.
In doing so, we also stop stressing about what we are supposed to DO in the world, on what our "delivery system" is (to use Plotkin's language), and start trusting that our seasons will unfold as they are meant to, just as the lilies of the field do, blooming, seeding, sowing, and pulling energy back into their roots, all in the right time without stressing about whether it will happen or what it will look like.