The theme of II John is that of false teachers. The nineteenth of the Epistles was written from Ephesus sometime around 93 AD by the apostle John; the last surviving of the 12 disciples of Jesus. They are still causing problems for the church, wandering around trying to convert people to follow them. John fears that these itinerant preachers might take advantage of the good hearted Christians, and so he warns them not to listen to those who do not speak the truth about Jesus.
"The elder unto the elect lady and her children, whom I love in the truth; and not I only, but also all they that have known the truth; for the truth’s sake, which dwelleth in us, and shall be with us for ever."
The identity of the "elect lady" is open to interpretation. Some think that she was a woman named Kyria (the Greek word for lady) and others that she was Jesus' mother, Mary. Most believe however, that the "elect lady" is a metaphor for the church and that her children would be the congregation