If any man doesn't obey our word in this letter, note that man, that you have no company with him, to the end that he may be ashamed.
And if any man obey not our word: The word "obey" means "to hearken to a command," that is "be obedient unto, submit to" (Thayer 638-1-5219). The term "word" here means the message Paul gives to the congregation in this epistle. He is instructing this congregation that if anyone does not obey the instructions of his letter, those in charge should take special note of him and deal with him decisively.