Adam Clarke Bible Commentary

I charge you by the Lord, that this epistle be read - There must have been some particular reason for this solemn charge; he certainly had some cause to suspect that the epistle would be suppressed in some way or other, and that the whole Church would not be permitted to hear it; or he may refer to the smaller Churches contiguous to Thessalonica, or the Churches in Macedonia in general, whom he wished to hear it, as well as those to whom it was more immediately directed. There is no doubt that the apostles designed that their epistles should be copied, and sent to all the Churches in the vicinity of that to which they were directed. Had this not been the case, a great number of Churches would have known scarcely any thing of the New Testament. As every Jewish synagogue had a copy of the law and the prophets, so every Christian Church had a copy of the gospels and the epistles, which were daily, or at least every Sabbath, read for the instruction of the people. This the apostle deemed so necessary, that he adjured them by the Lord to read this epistle to all the brethren; i.e. to all the Christians in that district. Other Churches might get copies of it; and thus, no doubt, it soon became general. In this way other parts of the sacred writings were disseminated through all the Churches of the Gentiles; and the errors of the different scribes, employed to take copies, constituted what are now called the various readings.