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. (ESV)

But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin. (KJV)

Greek: ἐὰν δὲ ἐν τῷ φωτὶ περιπατῶμεν ὡς αὐτός ἐστιν ἐν τῷ φωτί, κοινωνίαν ἔχομεν μετʼ ἀλλήλων καὶ τὸ αἷμα Ἰησοῦ τοῦ υἱοῦ αὐτοῦ καθαρίζει ἡμᾶς ἀπὸ πάσης ἁμαρτίας.

Transliterated Greek: ean de en tō phōti peripatōmen hōs autos estin en tō phōti, koinōnian echomen met’ allēlōn kai to haima Iēsou tou huiou autou katharizei hēmas apo pasēs hamartias.

Literal Word for Word Translation: 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.

Vocab: φωτὶ, phōti, light; περιπατῶμεν, peripatōmen, we should be walking; κοινωνίαν, koinōnian, we have fellowship; τὸ αἷμα Ἰησοῦ τοῦ υἱοῦ αὐτοῦ, to haima Iēsou tou huiou autou, (the blood, of Jesus, of the son, of him) the blood of Jesus, the son of him; καθαρίζει, katharizei, it cleanses; ἁμαρτίας, hamartias, of sin.

Commentary: Darkness is not a force that can oppose the light of God as some dualistic religions teach (Zoroastrianism, Star Wars, Taoism, Gnosticism, etc.). It is simply the absence of light. Have you ever seen darkness literally extinguish light? No! Darkness only appears when the light withdraws or an object blocks the light. The idea that the “dark side” and the “light” are in cosmic conflict was developed in ancient religions to explain the existence of evil (Manichaeism is an example – a religion followed by Augustine prior to his conversion to Christ). To the contrary, evil does not exist as its own power, but as a result of the darkness. People bump into things in the night because they cannot see. As well, people sin because they do not understand what they are doing. If they understood, they wouldn’t do it (hold on, I know some of you will disagree with that, but keep on reading as I elaborate). But of course, spending our growing years in darkness, we naturally sin and become pretty good at it. Over the years we find we are too much in the habit of certain sins and have difficulty stopping, even if we know better after being exposed to the light. Our bodies crave the excitement or thrill that comes from sin and it is difficult to stop. For one who has not been exposed to the light, it is impossible for them to stop sinning because they don’t understand sin given they are still in darkness. Yet, if we were born in the light, rather than in darkness, then fundamentally, we could understand sin from infancy and manage to avoid it. That was the situation with Jesus. He was human in every way that we are, and yet was without sin (Heb 4:15). It was because of His being born with the divine nature, the light, that He was able to not sin.

The light of God entails His righteousness, His character, and His holiness. Darkness is the opposite on all accounts. Being in the darkness is being in unrighteousness. All descendants of Adam and Eve are born in darkness, without knowledge of the light, and consequently are born unrighteous. We don’t have to commit one act of sin in order to be unrighteous. We are born that way. Think of it as being born blind. A blind person cannot gain sight by his own effort. His blindness hinders the possibility. So it is with being born in darkness. No one can come to the light on their own, especially given they don’t even know it exists having known darkness all their life. Rather, someone else must cure the blind man. God gave glimpses of the light through the prophets of the Old Testament. But it was Jesus who was the fullness of the light that came into the world to expose the darkness and sin so that people can realize they are not in God’s light and in need of sight – to see sin for what it is.

Verse 5 highlights that no one has fellowship with God while in the darkness. They can’t because He is the light. Since there is no darkness in Him at all, no one can be in the darkness and also be in God. Thankfully, John points out that those who walk in the light, as God is in the light, since He IS the light, do indeed have fellowship with one another and with Him. That light is the light of Christ. Many do not realize that when two people in a relationship, whether two who are married, parents and children, coworkers, church brothers and sisters, etc., that when they both are looking to the same God, bathing in the same light, truths, and righteousness, that they will be in harmony. That sounds ridiculous given the degree of disharmony among Christians today. But, do you think the disharmony is because there is conflict within Christ, or because of sin that persists in the relationships? James says in chapter 4 of his epistle, 1 What causes quarrels and what causes fights among you? Is it not this, that your passions are at war within you? 2 You desire and do not have, so you murder. You covet and cannot obtain, so you fight and quarrel. You do not have, because you do not ask. 3 You ask and do not receive, because you ask wrongly, to spend it on your passions. 4 You adulterous people! Do you not know that friendship with the world is enmity with God? Therefore whoever wishes to be a friend of the world makes himself an enemy of God. 5 Or do you suppose it is to no purpose that the Scripture says, “He yearns jealously over the spirit that he has made to dwell in us”? 6 But he gives more grace. Therefore it says, “God opposes the proud, but gives grace to the humble.” 7 Submit yourselves therefore to God. Resist the devil, and he will flee from you. 8 Draw near to God, and he will draw near to you. Cleanse your hands, you sinners, and purify your hearts, you double-minded. 9 Be wretched and mourn and weep. Let your laughter be turned to mourning and your joy to gloom. 10 Humble yourselves before the Lord, and he will exalt you. So, if we walk in the light, as He is in the light, we will have fellowship with God and with one another that is unlike any fellowship that is of the world.

Lastly, John says that if we are walking in the light, we are cleansed of all sin by the blood of Jesus. Notice it is ALL sin. There are two kinds of sin that keep us from God. First is the inherited sin, the unrighteousness that comes from being born in the darkness. Jesus took that away for all mankind. No man is barred from coming to Christ because of the inherited sin, if they will only realize it and know about Christ. The second type of sin is acts of sin. Those are the acts we do because we were born in darkness and tend to continue to do because of habit, even when we know better once we know Christ. But as we stay in the light, first, we are forgiven of those sins. As we realize the forgiveness, and are convicted by the Holy Spirit (our spiritual light), we desire to move away from our sins. When we see them correctly from God’s perspective, we will hate the sin and want to distance ourselves from it. Our sin is like onion layers. We manage to get past one kind of sin as the Lord works on us and we discover we have more. When we get weak and tired, old sins can come back. But, knowing we are forgiven gives us the assurance that we can get back up, and keep learning to walk in the light. The light in time will transform us day by day.

Without the light, we are destined to death apart from God – remaining in darkness. As the light came into the world through Jesus Christ, He took death and the sin that causes it, and buried it in a tomb from which He arose three days later. The sins of mankind and the death that result were left behind. Life emerged and we each have the right to place our individual sins at the cross, to crucify them, and to take the new life that comes from knowing Jesus Christ in faith – a faith that leads to repentance. Seeing sin for what it is, leads one to want to change. If not, we are still in darkness, as the next few verses will point out.