The apostle concludes this letter, 1. With an adjournment of many things to personal conference: Having many things to write unto you I would not write with paper and ink; but I trust to come unto you, and speak face to face, that our joy may be full. Here it is supposed that some things are better spoken than written. The use of pen and ink may be a mercy and a pleasure; but a personal interview may be more so. The apostle was not yet too old for travel, nor consequently for travelling service. The communion of saints should be by all methods maintained; and their communion should tend to their mutual joy. Excellent ministers may have their joy advanced by their Christian friends. That I may be comforted together with you by the mutual faith both of you and me, Rom 1:12. 2. With the presentation of service and salutation from some near relations to the lady: The children of thy elect sister greet thee. Grace was abundant towards this family; here are two elect sisters, and probably their elect children. How will they admire this grace in heaven! The apostle condescends to insert the nieces' duty (as we should call it), or dutiful salutation, to their aunt. The duty of inferior relations is to be cherished. Doubtless the apostle was easy of access, and would admit all friendly and pious communication, and was ready to enhance the good lady's joy in her nieces as well as in her children. May there by many such gracious ladies rejoicing in their gracious descendants and other relations! Amen.

The children of thy elect sister - Probably her own sister, who lived at Ephesus; and, being acquainted with the apostle's writing, desired to be thus remembered to her. Elect, both in this and the first verse, signifies excellent, eminent, or honorable. See on Jo2 1:1 (note).
Amen is wanting in the most ancient MSS., and in most of the versions; but ἡ χαρις μετα σου and μεθ' ὑμων, Grace be with thee, or with you, is found in several MSS. and versions.
Subscriptions in the Versions: -
The end of the Second Epistle. - Syriac.
The Second Epistle of John is ended. - Philox. Syriac.
Praise be to God for ever, Amen! - Arabic.
In the Manuscripts: -
The Second of John. - Codex Alexandrinus and Codex Vaticanus.
The Second of John to the Parthians. - One of Colbert's MSS.
The Second catholic Epistle of St. John the apostle and divine.
There are other subscriptions, but, like the above, they are worthy of little regard.

This epistle is more remarkable for the spirit of Christian love which it breathes than for any thing else. It contains scarcely any thing that is not found in the preceding; and out of the thirteen verses there are at least eight which are found, either in so many words or in sentiment, precisely the same with those of the first epistle. The most remarkable part of it is the tenth and eleventh verses, (Jo2 1:10, Jo2 1:11) relative to the orders concerning the heretical teacher; and from them we see how such teachers were treated in the apostolic Church. They held no communion with them, afforded them no support, as teachers; but did not persecute them.
On this model the conduct of all Christians should be formed, relative to the teachers of false doctrine in general. To go thus far, we have apostolical authority, to go farther, we have none. And let us still remember, in all cases it is our duty to love even our enemies, and consequently to do them any act of humanity and mercy.

The children of thy elect sister greet thee. Amen. Not the members of a sister church, as some think; but the children of one who was the sister of this lady, according to the flesh; and who, as she was either a very famous and excellent person, or rather one chosen of God likewise unto eternal life and salvation; and whose children also were walking in the truth, and here send their Christian salutation to their aunt; very likely those sister's children lived at Ephesus, where John resided.

ALFORD confesses that the non-mention of the "lady" herself here seems rather to favor the hypothesis that a Church is meant.

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