Jamieson, Fausset and Brown on 1 Thessalonians 4:11

11. study to be quiet--Greek, "make it your ambition to be quiet, and to do your own business." In direct contrast to the world's ambition, which is, "to make a great stir," and "to be busybodies" (2Th 3:11, 12).

work with your own hands--The Thessalonian converts were, it thus seems, chiefly of the working classes. Their expectation of the immediate coming of Christ led some enthusiasts among them to neglect their daily work and be dependent on the bounty of others. See end of 1Th 4:12. The expectation was right in so far as that the Church should be always looking for Him; but they were wrong in making it a ground for neglecting their daily work. The evil, as it subsequently became worse, is more strongly reproved in 2Th 3:6-12.