In these verses Paul pulls no punches as he gives instruction to the Thessalonians regarding Christians who are idle. A common view of this text is that people within the church became idle because they believed that the Lord would return immediately- and quit working to support themselves and their families. Actually, this is the way I was taught to understand it, but upon closer investigation, it seems unlikely.
Paul wrote about Jesus’ return in chapter 2. He writes about idleness here in chapter 3; why didn’t he link them together directly? What he actually did was to separate them, to place a bridge of transition in between and then raise a new subject, keeping these two points apart. If he wanted to tell people that Jesus wasn’t coming back any time soon (which he did NOT tell them) then it would have been a great deal more effective for him to have told them to get back to work in chapter 2. If you combine that with the fact that he wasn’t telling them that Jesus would return in a long time, he was writing to tell them He hadn’t come back yet; the notion of eschatology being the reason for the idleness seems very unlikely indeed.
A more likely approach to this text is that some had stopped working because the believing community of the first century was so generous with each other that they just didn’t feel it was necessary to work; thus, they were taking advantage of the generosity of others, placing an added burden on the ones who had to provide for them, which is no way to present the gospel to the larger community. Paul’s point here is that they must not allow this kind of behavior in the church.
Paul’s seriousness is evident right off the bat as he “commands” in the Lord’s name that this must stop (v. 6). In 7-9, Paul reminds everyone that when he was with them, he worked every day to pay for his own food, and that he did so as an example to be followed by all.
For even when we were with you, we gave you this rule: “The one who is unwilling to work shall not eat.” (3:10)
This verse makes a very clear point that one who is unwilling to work isn’t to be helped in the church. The New Testament writers, including Paul are very clear that the ones who are unable to work are to receive help of all kinds, and those who are in a temporary bad way are to be helped, but those who just want to be lazy are to be permitted to reap the harvest they have sown- for their own edification.
Verses 11-12 go on to mention that at least some of these idlers were using their leisure to insert themselves into the business of others, and of course that also must stop.
In the centuries that have passed, some have taken this as teaching for non-church governmental bodies and outside social policy, and this view misses the point of Paul’s message entirely. First, Paul is speaking of life within the church, not in the outside community. In the first century, there were some provisions made for the poor and destitute, although nothing like we have today in most places; Paul did not mention this or comment upon it at all. His instruction here is within the strict confines of church discipline and the way believers should behave.