Again Jesus spoke to them saying 'I am the light of the world, the one following me, no not walks in darkness rather has the light of life.' (John 8:12)
The one following me no not walk in darkness. No, οὐ (ou) objectively negates a statement "ruling it out as a fact." God is Light, this is a fact, "and this exists the message which we heard from him and proclaim to you; God is light and there is not one (ou "no, not" and heís, "one") darkness in him" (1 John 1:5). It is also true that "if we walk in the light like as he exists in the light, we have fellowship with each other..." (1 John 1:7).
"The people living in darkness have seen a great light, and on those living in the region and shadow of death, a light has dawned.” (Matthew 4:13-16)
It was prophesied that Jesus would come as a great light to the Gentiles. John writes, "in him was life, and that life was the light of men" ( John 1:4). Think about that, it was the life in him that was a light to men. Is it not so for us? that having abundant life as the fruit of abiding in him we are a light to the world. "The light shines in the darkness and the darkness not comprehending it" ( John 1:5). Paul writes "in their case the god of this world has blinded the minds of the unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God" (2 Corinthians 4:4). Jesus is the Light, and the gospel is about seeing the Light of the glory of God.
but now has been made known through the appearing of our Savior, Christ Jesus, on the one hand, in order to abolish death and, on the other, to bring to light life and incorruptibility through the gospel, (2 Timothy 1:10)
But you are a chosen race, a royal priesthood, a holy nation, a people for his own possession, so that you may declare the glorious deeds of the one who called you out of darkness into his marvelous light. (1 Peter 2:9)
Though we do not consider ourselves of the flesh no longer but of the Spirit, we do not ignore that we are still in a body in which sin dwells and evil is near. We allow the just judge, the truth, to judge sin done accordingly in the body, not in regards to judgment and condemnation and eternal separation from God but in regards to holiness and purity. Being called out of darkness into his marvelous light implies we declare glorious deeds from walking in the light. It implies to experience the fullness of life in this mortal body I must walk in the light. The purification of sin in the body becomes a testimony of those abiding in the light. As Paul writes this is the outcome of sanctification, being set apart from the world and the desires of the flesh; Life (Romans 6:22).
Jesus came to bring to light Life. Again we see that Life in Christ is the Light to men, incorrutable, eternal life that does away with death through the Word that endures for all time. Jesus was the Word that became flesh and dwelt among men, the glory of the only begotten son of God ( John 1:14). He is the word of life, whom they saw, heard, and touched and proclaimed to us eternal life (1 John 1:1-5). "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. If we say we have fellowship with him while we walk in darkness, we lie and do not practice the truth" (1 John 1:5-7). Ths light is proclaimed to us so that we too may have fellowship in the light and that our joy may be made complete (1 John 1:3-4). Now, John is also writing that we may not sin, but if we do, if we walk in darkness we have an advocate with the Father, and "If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness" ( 1 John 1:9).
Though we do not consider ourselves of the flesh no longer but of the Spirit, we do not ignore that we are still in a body in which sin dwells and evil is near. We allow the just judge, the truth, to judge sin done accordingly in the body, not in regards to judgment and condemnation and eternal separation from God but in regards to holiness and purity. Being called out of darkness into his marvelous light implies we declare glorious deeds from walking in the light. It implies to experience the fullness of life in this mortal body I must walk in the light. The purification of sin in the body becomes a testimony of those abiding in the light. As Paul writes this is the outcome of sanctification, being set apart from the world and the desires of the flesh; Life (Romans 6:22).
Can we comprehend what such Light is? Jesus is the only one having immortality, dwelling in unapproachable light, whom no one human, not one powerful like as him (1 Timothy 6:14-16). We can't comprehend what we will be, but we know one day we will be like him, so those who have such hope purify themselves just as he is pure (1 John 3:3). Walking in the Light is where a person in Christ belongs, "for you are all sons of light, sons of the day. We do not belong to night or darkness" (1 Thessalonians 5:5). God is light and in him is no darkness, if I do not walk in the light I am not yielding truth and I need to confess my sin, and get back into the Light. In the light all things are exposed, as there is no darkness in Him, thus to have fellowship with Him, is to be in the Light. Ask God for such wisdom, knowing all good gifts come down from the Father of lights in whom there is no shadowy thing.
"to open their eyes, so that they may turn from darkness to light and from the power of Satan to God, that they may receive forgiveness of sins and an inheritance among those sanctified by faith.." (Acts 26:18).
So to the lost Paul prays for God to open their eyes so they may turn from darkness to light. And to believers Paul prays for more enlightenment, "for this reason, because I have heard of your faith in the Lord Jesus and your love toward all the saints, I do not cease to give thanks for you, remembering you in my prayers, that the God of our Lord Jesus Christ, the Father of glory, may give you the Spirit of wisdom and of revelation in the knowledge of him, having the eyes of your hearts enlightened.. " (Ephesians 1:15-20). I think when John mentions that the mature are those who know him from the beginning, he speaks of those who abide in him and have walked with Jesus in the Light for some time, "the one claiming to abide in God is obligated to walk as Jesus walked" (1 John 2:6). John also equates walking in the Light to following the command of Jesus, the new commandment which was an old one, to love one another. "The one who loves his brother is living in the light and in him there is no cause for stumbling" (1 John 2:10).