1 John 2:18 - 3:6
Several thoughts come screaming out of today's New Testament passage. First, there are more than 1 anti-christ expected. John uses the plural and then uses one singular capitalized to signify that we can expect a great falling away of anti-christs who come from believers - insiders under the influence of Satan. Christians will always have their unbelievers, but having those with us that fall away can cause great division. A house divided cannot stand so we must prepare ourselves with the Truth so that we are not deceived. Also I draw attention to his definition of anti-christ - "And who is a liar? Anyone who says that Jesus is not the Christ. Anyone who denies the Father and the Son is an antichrist. Anyone who denies the Son doesn’t have the Father, either. But anyone who acknowledges the Son has the Father also." Notice that the argument is not around doctrine, tradition, and procedure, it is a simple charge of whether Jesus is the Christ or not. This is significant because many today want to exclude groups of Christians who don't agree with particular doctrinal positions that they feign are disqualifying for inclusion. This supports my contention of adiaphora - that the only essential requirement for inclusion in our faith in Christ is repentance, baptism of water and the Spirit, and faith in Christ and Christ crucified as stated in Roman's 10:9 - the rest is adiaphora ( important for discussion, but not essential for our salvation)!
Secondly, our inclusion in fellowship with the Father and Son are so dependent in our having the indwelling of the Holy Spirit. Notice in the passage that John attaches the promise and guarantee of eternal fellowship with the Holy Spirit and Truth. This makes perfect sense since the Holy Spirit is the discerner of Truth and this Truth is simple - Christ and Christ crucified is the sum and the whole of the Plan of Salvation. Why? Because it is the ONLY thing necessary to power justification, mercy, and grace. EVERYTHING else is superfluous! The very fact that the term strictly translated, anti-christ, "means against the anointed", is our prima facie (bold and incontrovertible) proof of the singularity concept of inclusion for Christianity- Christ and Him crucified. This is the simple doctrine that defines our faith and NOT any other doctrine! This is why John and Peter are clear about the simple Truth that we were taught from the beginning. The rest is adiaphora!
Finally, this is why blasphemy against the Holy Spirit is unforgivable in this world and the next ( Matt 12:30). Amen.