"5 This is the message we have heard from him and proclaim to you, that God is light, and in him is no darkness at all. 6 If we say we have fellowship with him while we walk in darkness, we lie and do not practice the truth. 7 But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin. 8 If we say we have no sin, we deceive ourselves, and the truth is not in us. 9 If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness."
In my estimation, one of the most important phrases in the New Testament is the term "in Christ". NT authors, Paul in particular, seem to equate sanctification with continuity in Christ.
Here we are told that in God there is "no darkness at all." Elsewhere we are told that we are in Christ, and Christ is in God, therefore we can reasonably conclude that we are to share Christ's status as "in God." And we are told that therein is no darkness at all.
Darkness symbolizes deceit, as well as rebellion, sin, and the death-state of unbelief. When we consider the metaphor, we know that darkness hides things, makes them invisible. In v. 6, walking in the darkness is contrasted against truth. Those who do not walk in the light, or in the truth, cannot expect to be in God, or by connection in Christ either.
There is a lot of power in the metaphor of light and darkness as John uses it. The person who is in the darkness does not want to come into the light for fear that his works will be exposed. Works = sins, in this instance. So there is shame, and guilt, in darkness. Elsewhere in 1st John we are told that fear has to do with punishment, so fear is also a factor when a person remains in the darkness. As evidenced by guilt, the person in darkness is well aware of their sin, and thus remains afraid of punishment.
In contrast, God is our supreme example of being in the light. In light each person is fully exposed. The opposites of shame, guilt and fear are justification, vindication and courage. God's very nature is to reveal, to expose, to declare, himself. The antipode of darkness.
So what of us, who, though we seek to be in Christ, are definitely still preserving traits of the darkness? There are none righteous; he who claims to be without sin is deceiving himself. How can we be in God?
The answer is found in Romans 4: "to the one who does not work but believes in him who justifies the ungodly, his faith is counted as righteousness." Jesus is our justification, vindication and courage. He is our priest and the one standing in our place. Since he is in perfect light, he dispels the darkness in us. The work is done, the key to living with the light in our own hearts is to love him. There is no fear in love, neither is there shame, or guilt.
Lastly, remember what love means. It is a conscious act of mind and heart, will and intellect, a love of the whole being, devoid of the falseness that emanates from darkness and often goes by the name of "feelings."
