‘He was not the light, but came that he might bear witness of the light, which was the true light, which lights every man coming into the world.'
The stress now is on the fact that John was not the light, but came to bear witness to the light. He pointed away from himself to Another. He was not himself ‘the Light' in the fullest sense of the word (although Jesus would later say that ‘he was a burning and a shining light' - John 5:35) because this coming light was unique, He would be the true and full light of God, ‘the light of the world' (John 8:12). Thus he, John, could only point away from himself to the light Who was coming, that men may believe in Him. Indeed the whole emphasis concerning John the Baptiser in this Gospel is on him as a witness to Jesus Christ.
It is significant that John has to point out that John the Baptiser was not the light. In the time of Jesus and the early church there were many followers of John the Baptiser (compare Acts 19:1-7), who followed John so intensely that they omitted to accept his witness and turn to Jesus. In a sense they were rivals to the early church. John wants men to see that if they follow the teaching of John it can only lead them to Jesus. But this very much emphasises the centrality of Hebrew thought in this passage. No one, not even John the Baptiser's closest followers, would have thought of John in terms of the Greek Logos.
‘Which lights every man coming into the world.' Whether ‘coming into the world' is to be attached to ‘every man' as signifying ‘lightens every man that comes into the world', thus applying it literally to ‘every man', or whether it should be attached to ‘the true light' as signifying ‘the true light --- that was coming into the world' is open to question. But both essential ideas are true, for He was certainly coming into the world, and He was equally certainly coming as a light to every man who was coming into the world. But the latter is more probably the essential meaning as normal Greek usage suggests. The Light had lightened all men at creation by making man a spiritual being, and was now coming into the world as the One Who lightens every man from a spiritual perspective. The offer was universal. Though not all would receive the light, it would shine on them, and by their response to it the truth about them would be revealed (John 3:19-21). Compare how Jesus is elsewhere constantly described as the One Who was ‘coming into the world' (John 6:14; John 9:39; John 11:27; John 16:28).
On the other hand we could see it as meaning that the Word was a universal light shining on every man, pleading for response, and yet soon fading as far as they were concerned as men closed their minds and hearts to Him. This thought is amplified by Paul in Romans 1:19-20. To those whose hearts are open to the light, Nature itself will reveal the truth about God's eternal power and Godhead.
Isaiah describes the Coming Servant of the Lord as being ‘a light to the Gentiles' (Isaiah 42:6; Isaiah 49:6), words which are cited in Luke 2:32 of Jesus, and this ties in with the idea of Him ‘lighting every man who comes into the world' rather than just the Jews. This may well indicate that Isaiah's prophetic ideas are foremost in his thoughts.
That this light refers to Jesus is immediately made clear (John 1:10-11; John 1:14) and also comes out later in the chapter where John the Baptiser bears his testimony to Jesus (John 1:29-34). It is testimony to how faithful the Gospel writer is to his sources that he does not try to put terms like ‘the Word' or even ‘the light' on the lips of John the Baptiser. But the reader is left in no doubt that Jesus is the One to Whom ‘the Word' and ‘the light' refer. (It is even more significant in that the Qumranists spoke of ‘the sons of light' and the ‘spirit of lights', so that John must have been aware of such terminology, and could well have used it, but of course their light was the light of the Torah as illuminated by the ‘good spirit' and by ‘the Teacher of Righteousness').