And if any one obeyeth not our word by this epistle (ei de ti ouc upakouei twi logwi hmwn dia th epistolh). Paul sums up the issue bluntly with this ultimatum. Condition of the first class, with negative ou, assuming it to be true. Note that man (touton shmeiousqe). Late verb shmeiow, from shmeion, sign, mark, token. Put a tag on that man. Here only in N.T. "The verb is regularly used for the signature to a receipt or formal notice in the papyri and the ostraca of the Imperial period" (Moulton & Milligan's Vocabulary). How this is to be done (by letter or in public meeting) Paul does not say. That ye have no company with him (mh sunanamignusqai autwi). The MSS. are divided between the present middle infinitive as above in a command like Romans 12:15 ; Philippians 3:16 or the present middle imperative sunanamignusqe (-ai and -e often being pronounced alike in the Koin). The infinitive can also be explained as an indirect command. This double compound verb is late, in LXX and Plutarch, in N.T. only here and 1 Corinthians 5:91 Corinthians 5:11 . Autwi is in associative instrumental case. To the end that he may be ashamed (ina entraph). Purpose clause with ina. Second aorist passive subjunctive of entrepw, to turn on, middle to turn on oneself or to put to shame, passive to be made ashamed. The idea is to have one's thoughts turned in on oneself.