6. we command you—Hereby he puts to a particular test their obedience in general to his commands, which obedience he had recognized in 2Th 3:4.
withdraw—literally, "to furl the sails"; as we say, to steer clear of (compare 2Th 3:14). Some had given up labor as though the Lord's day was immediately coming. He had enjoined mild censure of such in 1Th 5:14, "Warn … the unruly"; but now that the mischief had become more confirmed, he enjoins stricter discipline, namely, withdrawal from their company (compare 1Co 5:11; 2Jo 10, 11): not a formal sentence of excommunication, such as was subsequently passed on more heinous offenders (as in 1Co 5:5; 1Ti 1:20). He says "brother," that is, professing Christian; for in the case of unprofessing heathen, believers needed not be so strict (1Co 5:10-13).
disorderly—Paul plainly would not have sanctioned the order of Mendicant Friars, who reduce such a "disorderly" and lazy life to a system. Call it not an order, but a burden to the community (Bengel, alluding to the Greek, 2Th 3:8, for "be chargeable," literally, "be a burden").
the tradition—the oral instruction which he had given to them when present (2Th 3:10), and subsequently committed to writing (1Th 4:11, 12).
which he received of us—Some oldest manuscripts read, "ye received"; others, "they received." The English Version reading has no very old authority.