2 John
Second John is a single page, a note from the elder to the elect lady and her children, most likely a local congregation under the figure of a household. Its two concerns are inseparable: walk in love, and walk in truth. The commandment is not new but the one heard from the beginning, that we love one another. Yet love has a boundary: many deceivers have gone out who deny Jesus Christ come in the flesh, and the church must not give them a platform or a blessing. Brief as it is, the letter holds hospitality and doctrine in careful balance.
The elder, traditionally identified with John the apostle
AD 85–100
The elect lady and her children, likely a local congregation
To urge a congregation to continue in love and truth while refusing hospitality to teachers who deny Christ's incarnation.