I believe that all areas of our lives need some flexibility. Our bodies need it to move, or minds need to be flexible to learn, and faith needs flex to withstand life. I overheard someone likening their faith to concrete the other day, but that struck me as a particularly bad metaphor.
Concrete is hard, cold, brittle, dirty, heavy, and bland. It is also incredible inflexible and vulnerable to shifts in the weather and the soil beneath it. For me, faith needs to be something lighter, warmer, and far more flexible. It needs room to grow and it must change with the times, with our development or it cracks and crumbles leaving us exposed and vulnerable. For me, I think faith is more like a garden- it has its seasons and its own rhythm. It changes and grows and leaves me room to roam and enjoy it, but it is never stiff or hard.
I don't know how other people envision their faith, but concrete, while on the surface seems strong, just doesn't seem to be a good thing to aspire to. I'd love to hear your thoughts and metaphors, though.