Various models of the timing of this last day and hour are discussed under -telos- (1 Corinthians 10:11) and -parousia- (1 Thessalonians 4:15 & 2 Thessalonians 2:1,8). The model I prefer is that the early Christians expected, as Jesus had predicted, a Day of the Lord when he would come to topple the temple and city of Jerusalem (Matthew 24:28, 30, 37, exactly as he had in His coming to topple Babylon, Isaiah 13:6-13). This coming would occur in that generation (Matthew 23:36, 24:34), as in fact occured in AD 70.
The first Epistle of John therefore seems to be written in the -eschaty
ora- the last hour before that traumatic event for the Jewish people
(2:18). Jesus had predicted that the event would be preceded by
the emergence of -pseudochristoi kai
pseudoprophytai- false messiahs and false prophets (Matthew 24:24, see 24:5, 23, 26). And in his letter John says that, as expected -antichristoi polloi gegonasin- many Christ opposers had already emerged (2:18).
John defines an -antichristos- as a Christ opposer, who says that -Iysous ouch estin o Christos- Jesus is not the Messiah (2:22). In other words -o arnoumenos ton patera kai ton uion- such a person denies the Father and Son relationship in the Godhead (2:22)
When the Epistle was written the world also abounded with - psudoprophytai-
false prophets (4:1). Some of these made their way into the -ekklesiai-.
Others emerged from a church (as Paul said would happen in Ephesus, Acts
20:29,30). All false
prophets were moved by -to tou antichristou- the spirit of opposing the Messiah (4:3). This was why it was so important for church congregations to -dokimazein- test the spirits of those who claimed to speak God's message (4:1). A true prophet would confess that -Iysoun Christon en sarki elyluthota ek tou theou- Jesus was the Messiah and that he had come from God and taken birth in human flesh (4:2-3).
It makes easier sense to base our interpretative model on what John wrote in his Gospel to explain the best known verse in the Bible (John 3:16). The Son of God is not in the business of condemning anyone (John 3:17). -auty de estin y krisis- but for the whole of humanity there is a critical dividing line (John 3:19). Some love -to phos to alythinon, o photizon panta anthropon- the true light which illuminates every single person in the world (John 1:9). That light became visible in the life and death of Jesus. The evil person -misei to phos kai ouch erchetai pros to phos- hates that light and shrinks away from it.
With that model in mind, we welcome badly behaved sinners to communion,
warts and all (1 John 5:17). But if a person quite obviously hates
the light of God, and Jesus in particular, there is -amartia pros ton
theon- deadly eternal sin (5:16). There is no point in praying
for forgiveness and superficial improvement. What is needed is total conversion.
As the Lord said to Paul, his job was "to open their eyes so that they
turn from darkness to light and from the power of Satan to God, so that
they may receive forgiveness of sins and a place among those who are sanctified
by faith in me" (Acts 26:18). Welcoming ordinary sinners to our
congregation is one thing, turning outsiders from commitment to the darkness
(John 3:19) is another. And I don't think either task is easier
than the other.