When I was a kid, I used to get these awful pains in my knees, especially at night when I was trying to go to sleep, or at least that is when I noticed the pain. I was always told that they were growing pains, and so I bore through them, because I knew that I would be taller as a result.
I still feel like I get those growing pains, more figuratively than literally. I get into a zone of comfort, where everything seems to be going okay, and then something jabs me, like a sharp pain in my knees (again, a metaphor), to make me shake out of the comfort and remember that I'm not the one controlling my life. There isn't anything terrible going on in my life right now...we've just been studying Joseph in my Bible study, and we've talked a lot about how we should remember God. We get caught up in our own lives and forget Him. For some people, we forget Him when times are good, like me, and call on Him when we find ourselves in trouble. For others, it's a matter of forgetting about Him when times are bad. A gal in the Bible study mentioned how one of our biggest enemies can be comfort...we skip along, bluebird on my shoulder style, and God is sitting there, going "Hey you! Remember me? The One who brought the good into your life? I'm going to let this little thorn come in to shake you out of this stupor, to bring you back to Me."
So, the growing pains - that jab of reality that says that we need to pause and remember. Whatever our own personal thorn is, it makes us think back on how God has carried us through similar situations, how He has been gracious in the past, how He has always provided for us, and how He will take care of us through this pain. And, after a time, the pain eases, but hopefully we won't forget Him when it does.