The Apostle John And His Writings
IV. The Second Epistle of John
The Second and Third Epistles of John are two very short books addressed to individuals.
The Second is "to the elect lady and her children, whom I love in truth, and not I only but also all who have known the truth", and the Third is "to the beloved Gaius, whom I love in truth". Both speak about receiving and not receiving. The sister and her children were instructed regarding whom they were not to receive in their home. As Christians we are told to love one another and love is something that is much stressed, particularly in the writings of John. In these epistles we read of "love in truth", for this love is not the emotional and sentimental love often spoken of today. "Love in truth" is something different. If someone came who did not bring sound doctrine regarding the Person of Christ, or someone who thought he had some advanced knowledge that nobody else had, that he had learnt a little bit more, and so on, the sister was instructed not to receive him or have anything to do with him, she was not to even show him the common courtesy of greeting him that would express fellowship in any way.
There is no mention of the Assembly as such in 2 John but the individual Christian, and even the sister with children (we would assume a widowed sister) were to use this kind of judgment. The Lord must be first. Faithfulness to Him is paramount. This is true love. Love in truth does not make exceptions when there is someone who does not bring sound doctrine as to the Person of Christ.
John emphasizes in both these epistles how he appreciated his spiritual children (and we certainly can apply it to literal children as well) walking in truth. As parents, this is one of the things we appreciate about our children, and it is one of the griefs of heart of many parents when their children are not walking in truth. John speaks of those to whom he stood in relationship as an older one. He does not speak of His apostolic authority here, he wrote the epistles as "the elder".
He had a love, an interest in younger believers, not only that they were saved and would go to heaven, but that they walked in truth.