Beloved, do not believe every spirit, but test the spirits to see whether they are from God; for many false prophets have gone out into the world.
By this you know the Spirit of God: every spirit that confesses that Jesus Christ has come in the flesh is from God,
and every spirit that does not confess Jesus is not from God. And this is the spirit of the antichrist, of which you have heard that it is coming; and now it is already in the world.
References for 1 John 4:3
Little children, you are from God, and have conquered them; for the one who is in you is greater than the one who is in the world.
They are from the world; therefore what they say is from the world, and the world listens to them.
We are from God. Whoever knows God listens to us, and whoever is not from God does not listen to us. From this we know the spirit of truth and the spirit of error.
Beloved, let us love one another, because love is from God; everyone who loves is born of God and knows God.
Whoever does not love does not know God, for God is love.
God's love was revealed among us in this way: God sent his only Son into the world so that we might live through him.
In this is love, not that we loved God but that he loved us and sent his Son to be the atoning sacrifice for our sins.
Beloved, since God loved us so much, we also ought to love one another.