1 John 4:4-6

4 You are of God, little children, and have overcome them; because greater is he who is in you than he who is in the world.  5 They are of the world. Therefore they speak of the world, and the world hears them.  6 We are of God. He who knows God listens to us. He who is not of God doesn't listen to us. By this we know the spirit of truth, and the spirit of error.