The third sign

John writes in the chaos following a church schism to tell disciples of Jesus how to discern between genuine and false Christianity.

1. The first criteria is the belief that Jesus was, not only the Son of God (5:5 and 13), but was also fully human (1 John 4:2-3, and 1:1-4).

2. The second evidence is that the true Christian will obey Jesus’ commands: "if anyone obeys his word, love for God is truly made complete in them" (1 John 2:5).

3. And the third criteria is the very essence of Jesus’ commands;

"And this is the command: to believe in the name of his Son, Jesus Christ, and to love one another as he commanded us" (1 John 3:23).

"Dear friends, let us love one another, for love comes from God. Everyone who loves has been born of God and knows God. Whoever does not love does not know God, because God is love. This is how God showed his love among us: he sent his one and only Son into the world that we might live through him. This is love: not that we loved God, but that he loved us and sent his Son as an atoning sacrifice for our sins. Dear friends, since God loved us, we also ought to love one another. No one has ever seen God; but if we love one another, God lives in us and his love is made complete in us" (1 John 4:7-12).

John is not telling us that to be a genuine Christian you must be perfect. (At least three times in the letter he tells us what to do if and when we sin.)

John is explaining that genuine Christianity is evidenced by the belief that Jesus is fully God and fully human and by a life committed to obeying Jesus’ command to love one another.

Every person who believes this and whose life demonstrates this is a genuine Christian.

This is of course exactly what Paul wrote in Galatians 5:6; "the only thing that counts is faith expressing itself in love."