1 John 2:18-29 Children, it is the last hour, and as you have heard that antichrist is coming, so now many antichrists have come. Therefore we know that it is the last hour. (19) They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us. (20) But you have been anointed by the Holy One, and you all have knowledge. (21) I write to you, not because you do not know the truth, but because you know it, and because no lie is of the truth. (22) Who is the liar but he who denies that Jesus is the Christ? This is the antichrist, he who denies the Father and the Son. (23) No one who denies the Son has the Father. Whoever confesses the Son has the Father also. (24) Let what you heard from the beginning abide in you. If what you heard from the beginning abides in you, then you too will abide in the Son and in the Father. (25) And this is the promise that he made to us—eternal life. (26) I write these things to you about those who are trying to deceive you. (27) But the anointing that you received from him abides in you, and you have no need that anyone should teach you. But as his anointing teaches you about everything, and is true, and is no lie—just as it has taught you, abide in him. (28) And now, little children, abide in him, so that when he appears we may have confidence and not shrink from him in shame at his coming. (29) If you know that he is righteous, you may be sure that everyone who practices righteousness has been born of him.
In studying God's Word, we sometimes bring in our own understanding of what a particular word means and import this meaning into the text. The result being we force the text to say what we want instead of hearing what the author intended to say. In this passage we have two very popular words in Christian circles, anointing and antichrist. But we need to understand how John uses these words and what he is trying tell his original readers and how that applies to us.
In the previous sections, John urges us to walk with God, keep his commandments, love one another and stay away from the temporal desires of this world. John also clearly distinguishes between those in the light and those who are not. Those in the light are cleansed by the blood of Jesus Christ (1:7), have fellowship with God (1:6), have fellowship with one another (1:7), keep God's commandments (2:5), are characterized by love for each other (2:9) and do not love the world (2:15). Those in the darkness are deceiving themselves (1:8), have no fellowship with God (1:6), do not have the truth in them (1:8), do not keep God's commandments (2:4) and love this world (2:15).
In this passage, John again contrasts two groups of people. Those anointed by the Holy One (2:20) and the antichrists who started as part of the body of Christ (2:18,19).
They are the church
They came from the church and they show that they were never truly part of the church by leaving. (18,19)
The know the truth and have all knowledge (20-21) i.e Jesus is the Christ, the word of life through whom we have fellowship with God and eternal life
They are liars who do not know the truth
They deny Son (22-24)
They deny the Father (22-24)
They deny the truth that was heard from the beginning (24)
They will not be deceived because the anointing by God teaches them the truth, if they abide in what they have heard from the beginning (27-28)
They try to deceive the anointed (26)
We see here that all Christians who are part of the church of Christ have the anointing. It is the power of God that keeps us rooted in the gospel as it teaches us more and more about Christ.