Times were hard for the Thessalonian believers. To their credit, they loved each other and continued to do good, in spite of their confusion about the Day of the Lord. Paul commended them for their commitment to the Truth, reminding them that the Holy Spirit was working in and through them and that they were able to stand firm on what Paul and Timothy taught them through the Sciptures. He offered a benediction that God would comfort and establish them in goodness.
At this point, it seems like Paul was wrapping up the letter when he remembered something else. It’s a “but wait, there’s more” moment.
Paul carefully balances recognition of what the church as a whole is doing well with a direct admonition to the busybodies who caused trouble and refused to work. In a quick shift, Paul turns from the distant future (eschatology) to the immediate present. Perhaps it was the influence of the false teachers that caused some individuals to quit working and become both freeloaders and busybodies, but Paul admonished them, saying that those who were unwilling (not unable) to work should not eat. Instead, they should be encouraged to do their work quietly and earn a living, just as Paul and Timothy had done.
Finally, Paul encouraged the people to “not grow weary in doing good.” When life is hard and nothing makes sense, we must choose to do good anyway. We can trust the Father and be encouraged that we are being set apart for His glory. The Lord is faithful and will establish His own in peace and grace through Jesus.