Verse 22c: Such a Person is the Antichrist
Who is the liar? It is whoever denies that Jesus is the Christ. Such a person is the antichrist—denying the Father and the Son.
John warns his beloved children that many antichrists have risen up from among their ranks in these last hours (2:18) and admonished them to remember that they left the Church because they did not belong to Christ (2:19); they did not love their brothers and sisters in Christ, nor did they accept the testimony of Christ, therefore they rose up with destructive heresies and betrayed the body of Christ that they once claimed to have fellowship with.
“Such a person is the antichrist—denying the Father and the Son”: the person who denies that Jesus is the Christ has denied the Father and the Son because they are One:
John 6:40 (CSB) For this is the will of my Father: that everyone who sees the Son and believes in him will have eternal life, and I will raise him up on the last day.”
John 12:45-46 (CSB) Jesus cried out, “The one who believes in me believes not in me, but in him who sent me. 45 And the one who sees me sees him who sent me.
John 14:9 (CSB) Jesus said to him, “Have I been among you all this time and you do not know me, Philip? The one who has seen me has seen the Father. How can you say, ‘Show us the Father’?
Why does rejecting Jesus as Savior constitute rejecting the Father?
Because there is no other Savior except Yahweh:
Isaiah 43:11 (HCSB) I, I am Yahweh, and there is no other Savior but Me.
Jesus is Yahweh incarnate. Our Creator took on flesh, entered his creation with grace upon grace, and shed his blood to buy back those who were lost to sin. It is the Antichrist spirit who refutes this doctrine and refuses to accept that Jesus is the Messiah of the whole world.
Therefore,
1st Timothy 4:10 (CSB) For this reason we labor and strive, because we have put our hope in the living God, who is the Savior of all people, especially of those who believe.
There is One God, who alone occupies the office of Savior for all people and gives the benefit of his salvation to those who believe in Christ.
Unfortunately, many mistakes are made with this verse: firstly, the word “savior” is mistakenly treated as a verb instead of a noun, suggesting that God will “save” all people, but “savior” is a noun, meaning that God is the only one in whom Salvation may be found. Secondly, the phrase “especially those who believe” is mistakenly treated as suggesting that Christians will be some kind of elite class among the saved, but the word “especially” carries the meaning of “chiefly”, meaning that the chief benefit of God’s salvation is received by those who believe; we receive an inheritance in Christ.
The full force of the gospel says that anyone who rejects Christ as their Messiah has the spirit of the antichrist in them and has not received the anointing of the Holy One.
This warning was given to spare the beloved children of God from being deceived by those who do not have Christ.
Biblical Reasons 