People call John the Apostle of Love, but I think we could also call him the Apostle of Black and White, because he puts everything in black and white. You will not find gray in his writings. Consider the following, which serves as a way of revealing to us whether we are walking in darkness or not,

But he who hates his brother is in darkness and walks in darkness, and does not know where he is going, because the darkness has blinded his eyes (1 John 2.11).

If you hate your brother, you are walking in darkness. I do not know how John could have put it plainer. You either hate your brother and walk in darkness, or the opposite would be that you love your brother and walk in light.

Are you walking in darkness or light?