In Christ Jesus - Through Christ Jesus; or in connection with your love to him; that is, as Christians. This is an expression of tender regard to them as Christian brethren; of his love for the church; and his earnest desire for their welfare. It is in accordance with the usual manner in which he closes his epistles; and it is especially tender, affectionate, and beautiful here, when we consider the manner in which he had been treated by many of the Corinthians; and as following the solemn declaration in 1 Corinthians 16:22. Paul loved them; loved them intensely, and was ever ready to express his affectionate regard for them all, and his earnest desire for their salvation.
The subscription to the Epistle, “The first epistle to the Corinthians,” etc., was evidently written by some other hand than that of Paul, and has no claim to be regarded as inspired. Probably these subscriptions were added a considerable time after the Epistles were first written; and in some instances evidently by some person who was not well informed on the subject; see the note at the end of the Epistle to the Romans. In this instance, the subscription is evidently in its main statement false. The Epistle bears internal marks that it was written from Ephesus, though there is every probability that it was sent by three of the persons who are mentioned here. It is absurd, however, to suppose that Timothy was concerned in bearing the Epistle to them, since it is evident that when it was written he was already on a visit to the churches, and on his way to Corinth; see the notes on 1 Corinthians 16:10-11; 1 Corinthians 4:17. There is not the slightest internal evidence that it was written from Philippi; but everything in the Epistle concurs in the supposition that it was sent from Ephesus. See the introduction to that Epistle. There is, however, a considerable variety among the manuscripts in regard to the subscription; and they are evidently none of them of any authority, and as these subscriptions generally mislead the reader of the Bible, it would have been better had they been omitted.