This is the message we have heard from him and declare to you: God is light; in him there is no darkness at all. If we claim to have fellowship with him and yet walk in the darkness, we lie and do not live out the truth. 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, purifies us from all sin.
1 John 1:5-7
This section is given context in verse 5: God is light; in him there is no darkness at all. Thus, this section is all about John’s declaration of light versus darkness, and it contains comparisons and contrasts.
Before we take a look at it, keep in mind what John wrote in John 1:4 “In him was life, and that life was the light of men.” All through the Gospel story, John used “light” as signifying the presence of Jesus, contrasted with “darkness” denoting His absence. Keeping this in mind, let’s take a look at our text. After proclaiming that God is light, John gets down to his explanation by asserting that if we claim to be in fellowship with God, but walk in darkness, we lie, and are not in the truth. This is a rather easy statement to understand, for if we are in darkness, then we aren’t in His presence, and if we aren’t in His presence, we couldn’t possibly be in fellowship: There is no half-way.
The contrast is that if we walk in the light, as He is in the light, we have fellowship… because we are with Him in the light. If we have this fellowship in the light of His presence and truth, then His blood purifies us from all sin. The reality of the statement is that we can’t be in fellowship with Him until our sins have been forgiven by His sacrifice on the cross.
Sometimes, we may walk a ways in darkness, and by this I mean that we may stray from time-to-time. John doesn’t suggest that our errors kick us out of fellowship as we will see a little farther through this text, but that there is a way to return to the light of His presence, by confessing our sins, as we see in the next paragraph:
If we claim to be without sin, we deceive ourselves and the truth is not in us. If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness. If we claim we have not sinned, we make him out to be a liar and his word is not in us.
1 John 1:8-10
I think we all would agree that a claim by any one of us to have never sinned would be little short of crazy. John seems to think it’s worse than that. All have sinned, but take heart, for there is a way out, confess your sins and He will forgive; this is our covenant promise. There is simply no need for us to wring our hands and carry around a burden of guilt and shame before God, for when we confess our sins (acknowledge them) He will forgive; we have His Word on that!