In so many of Paul's letters to the various churches around the Mediterranean, Paul is admonishing and correcting the recipients of some bad behavior, bad theology or trying to solve some theological argument. This is not so in his letter to the Thessalonians. This is a letter of encouragement. It seems that the Thessalonians were good, strong Christians and their only real problem was persecution from those outside the faith. As such, I always find the letters to the Thessalonians particularly encouraging.
For those of us who consider ourselves to be faithful, and we really try to be as faithful as we can as often as we can, life can get pretty discouraging. We can get caught up in routines, we can feel like as much as we try to do the "right thing" so often that right thing goes unappreciated or unnoticed. If we get caught up in that, it really becomes difficult to do the right thing constantly when so many others don't do the same and seemingly their decisions that are based on selfishness or greed don't really seem to matter either. If you've ever felt that way, then Thessalonians is for you.
While none of us consciously are "keeping up with the Jones'" we can so easily wonder why we are striving so much to be faithful when it, frankly, doesn't seem to benefit us - or at least it seems that way. I wonder if the people of Thessalonica had any idea of their reputation that Paul is reporting to them? Did they know their example was a witness to all? Did they realize the impact they were having on other communities by their faithfulness to God? My guess is, probably not. Since communication and travel in those days was not what it is now, my guess is Paul's letter of encouragement really was welcome and inspiring. He let them know that their faithfulness, their choosing to do the right thing, really mattered.
My guess is it is the same for us. While we don't often receive accolades for the decisions we make or the way we live our lives, often it is others to are impacted by our actions... even if we aren't aware of it. We might not ever realize the witness we are to others, but we must keep on and keep the faith - people do notice, and most importantly, God notices. We will receive a reward for our decisions and our lives, we just may not see that now.
Keep the faith.