6-7If we claim that we experience a shared life with him and continue to stumble around in the dark, we're obviously lying through our teeth—we're not living what we claim. But if we walk in the light, God himself being the light, we also experience a shared life with one another, as the sacrificed blood of Jesus, God's Son, purges all our sin.
What does it mean to “walk in the light”?
What is “the light”?
The preceding verses in 1 John 1 answer the second question clearly;
So God is light.
Jesus came to the earth as God in human flesh. He was God, the light, in the world. There are several times in the Bible where Jesus refers to Himself as the Light of the world;
12Once more Jesus addressed the crowd. He said, I am the Light of the world. He who follows Me will not be walking in the dark, but will have the Light which is Life.
46I have come as a Light into the world, so that whoever believes in Me [whoever cleaves to and trusts in and relies on Me] may not continue to live in darkness. 47If anyone hears My teachings and fails to observe them [does not keep them, but disregards them], it is not I who judges him. For I have not come to judge and to condemn and to pass sentence and to inflict penalty on the world, but to save the world.
1IN THE beginning [before all time] was the Word (Christ), and the Word was with God, and the Word was God Himself. 2He was present originally with God. 3All things were made and came into existence through Him; and without Him was not even one thing made that has come into being. 4In Him was Life, and the Life was the Light of men. 5And the Light shines on in the darkness, for the darkness has never overpowered it [put it out or absorbed it or appropriated it, and is unreceptive to it]. 6There came a man sent from God, whose name was John. 7This man came to witness, that he might testify of the Light, that all men might believe in it [adhere to it, trust it, and rely upon it] through him. 8He was not the Light himself, but came that he might bear witness regarding the Light. 9There it was--the true Light [was then] coming into the world [the genuine, perfect, steadfast Light] that illumines every person.
5For what we preach is not ourselves but Jesus Christ as Lord, and ourselves [merely] as your servants (slaves) for Jesus' sake. 6For God Who said, Let light shine out of darkness, has shone in our hearts so as [to beam forth] the Light for the illumination of the knowledge of the majesty and glory of God [as it is manifest in the Person and is revealed] in the face of Jesus Christ (the Messiah).
It seems clear that if God is light, and Jesus is the light of the world, then to “walk in the light” would mean to walk, to live in, to abide in, Jesus, and in the knowledge of, and relationship with Jesus. This idea is confirmed in the same verse that we are looking at;
As we walk in the light, abiding in Jesus, any righteousness in us is displayed in the light of truth; it is God’s work in us, not our own.
21But he who practices truth [who does what is right] comes out into the Light; so that his works may be plainly shown to be what they are--wrought with God [divinely prompted, done with God's help, in dependence upon Him].
But anyone working and living in truth and reality welcomes God-light so the work can be seen for the God-work it is.
As always, the focus should be on Jesus, not on us or our self-righteous actions.
They searched the Scriptures day after day to see if Paul and Silas were teaching the truth.
But is this what “the light of the world” does?
The truth is found in the context of the verse. Jesus declared that He was the light of the world right after He had told the woman caught in the act of adultery, “Woman, where are those accusers of yours? Has no one condemned you?”
When she said, “No one, Lord”, He said to her, “Neither do I condemn you; go and sin no more.” Then, the Bible tells us that “Jesus spoke to them again, saying, ‘I am the light of the world…’” (John 8:10–12)
How wonderful it is to know that when Jesus said, “I am the light of the world,” His light was not to show up the woman’s sin because He had just told her that He did not condemn her.
This tells us that we don’t have to be fearful when we come into God’s presence. He is not there waiting to punish us for our mistakes and failures. His light is not for exposing our sins and shame, or for condemning us. No, His glorious light is for showing us how perfectly His Son’s blood has washed away our sins! That is why Jesus could tell the woman that He did not condemn her — because He would be condemned for her sin as well as ours at the cross.
Beloved, Jesus’ light unveils the truth that our sins have been completely removed. It reveals how perfect and spotless we are because of Christ’s perfect work at the cross. When you know this, you can go boldly into God’s presence, knowing that you have the light of life that gives you grace and hope!”