“Brothers, I write no new commandment to you, but an old commandment which you had from the beginning. The old commandment is the word which you heard from the beginning. Again, I write a new commandment to you, which is true in him and in you; because the darkness is passing away, and the true light already shines. He who says he is in the light and hates his brother, is in the darkness even until now. He who loves his brother remains in the light, and there is no occasion for stumbling in him. But he who hates his brother is in the darkness, and walks in the darkness, and doesn’t know where he is going, because the darkness has blinded his eyes.”
1 John 2:7-11

The old commandment and the new commandment are the same thing. We are to love each other as sisters and brothers in Christ. The new commandment is true in the life of the Christian, because the darkness of sin and the life of sin is passing away. As we make progress in the Lord, and in our spiritual walk with Jesus our Saviour, the darkness dispels and we walk in clearer and clearer light.
The more we love each other, the more light we have and the more light we show. Jesus is the Light of the World, because as the holy Lord and God, He is all light and there is no darkness in Him at all. As the Lord Jesus sets up, His kingdom on earth, the light grows and is growing until the kingdom will come. The darkness is passing away, because the light is shining. Every place where the light shines, the darkness is chased away.
The Christian brings light wherever they go. The mark of Christ is love for others and love especially for each other. When we live rightly and seek holiness in all we do and say, we bring light into the dark places of this world, where God would have us to be. We become light bearers and a blessing to the places and people that God sends us to.
We have no excuse and must make no excuse about hating a brother or sister in Christ, whatever they do. We must forgive those who do evil against us and say all manner of evil, falsely and ignorantly about us. This is the way of Christ. We may not be able to be close friends with that person, but we do not hate them. Some deeds done against us are very serious and some people need to be away for each other, but we do not hate.
Loving regardless and forgiving regardless, is a Christ like thing to do, and demonstrates we are walking in the light and have fellowship with God. We walk in the light and remain in the light. Because we walk in the light, we do not make mistakes and we are obedient in following what God wants us to do.
The opposite is also true. If we are hating people and being unforgiving and harsh, then we are walking in the dark, and not with God. We stumble and fall and fail because God is not blessing us and not pleased with us. We cannot see where we are going without the light, and so we get into a mess. We are blind to what we are doing and don’t see our own sin. It’s time then for self- examination.
We judge others but not ourselves, our at least, judge ourselves more leniently that other people. It is hard not to be biased when it comes to ourselves. God knows the end for the beginning and He will bring all things to pass and to light. He will vindicate the guiltless and convict the guilty. There is justice with God.
Jesus has brought the light into the world and has brought the gospel,that saves people and can rescue them for sin and death. Hate has no place in this gospel. The call is to everyone who believes. Everyone who hates has no salvation because the light cannot be there. When the light comes into a life, is brings light and the darkness goes and doesn’t hang around. Sin is not tolerated, as our desires are now for the light.