In the first century, deceivers and false brethren plotted to steal the sheep away from the Shepherd. These were antichrists, whom John’s audience heard “is coming” and “now many antichrists have come” (v18). In fact, the very existence of these men proved that it was “the last hour” (v18). The antichrists were denying the Father by denying the Son (v22-23) and trying to deceive believers (v26). Add to those charges the tragedy that they came not from without, but from within the very fold they were trying to deceive (v19), and we can relate to the fears and anxieties of first century Christians.
But John, by the inspiration of the Spirit, is not aiming to leave his readers in despondency. In fact, even as he warns of antichrists, John’s disposition is not one of doom and gloom but of hope and encouragement. He refers to his recipients as “children”, writing from a pastor’s heart. He writes of a sharp contrast between those antichrists and the true believers: they have denied the faith, but you know the truth. He encourages them by reminding them of who they are and what they have in Christ: “you have been anointed by the Holy One” (v20), “you have all knowledge” (v20), “you know [the truth]” (v21), you have the “promise that he made to us – eternal life”, and the anointing “abides in you” and “teaches you about everything” and “is true” (27).