1 John 4:5–6
They are of the world: therefore speak they of the world, and the world heareth them.
We are of God: he that knoweth God heareth us; he that is not of God heareth not us.
Hereby know we the spirit of truth, and the spirit of error.
John now draws a very simple line of distinction.
There are voices that belong to the world, and there are voices that belong to God.
Those who are of the world naturally speak the language of the world. Their message fits comfortably with the world’s thinking. Their ideas appeal to human pride, human wisdom, and human desire. Because of that, the world listens gladly. The message sounds familiar. It sounds agreeable. It sounds safe.
But John says something very different happens when a person truly knows God.
Those who know God recognize the voice of God when they hear it. They are drawn to His truth. They respond to His Word. Something inside them bears witness that what they are hearing is right.
That makes sense, because the same Spirit who inspired the Scriptures also lives within the believer. When the Word is opened and taught, the heart that belongs to God recognizes it.
Think about that.
You can often tell a great deal about a person by what they are willing to hear. A heart that knows God is drawn to the Scriptures. It may struggle, it may wrestle, but it keeps coming back to the Word because something inside knows it is life.
On the other hand, when someone consistently avoids the Word, minimizes it, or treats it lightly, that tells its own story.
John says this becomes one of the clearest ways to discern the difference between truth and error.
And remember what he has already told us in this chapter. The Spirit of truth always honors who Jesus truly is. It affirms that Jesus Christ came in the flesh. It holds firmly to both His humanity and His deity. It leads people toward the living God and toward the Scriptures that reveal Him.
But the spirit of error does the opposite. It diminishes Christ in some way. It subtly pushes people away from God. It makes light of the Word or replaces it with human ideas.
You need to see this.
In just a few lines, John gives the church a remarkably clear test. If a teacher lifts up Jesus as both God and man, draws people nearer to the Lord, and points them continually back to the Scriptures, the Spirit of truth is at work.
But if Christ is reduced, if the Word is sidelined, and if people are left farther from God rather than closer to Him, John says we are hearing something very different.
That is how we recognize the spirit of truth and the spirit of error.