15 "(John bore witness about him, and cried out, “This was he of whom I said, ‘He who comes after me ranks before me, because he was before me.’”)16 And from his fullness we have all received, grace upon grace. 17 For the law was given through Moses; grace and truth came through Jesus Christ.18 No one has ever seen God; the only God, who is at the Father's side, he has made him known."
John 1:15-18
Two further points remain for comment in these verses. First of all, the phrase in 16, 'grace for grace'. The RSV translates 'grace upon grace', while the Greek reads 'grace instead of grace'. What John means is that in the fullness that we receive in Christ, God gives us a constant supply of grace, grace that is succeeded by more grace, to meet every need that arises. Grace for every fresh situation, every new crisis, that arises in our lives; His is a full and sufficient salvation. It is not possible to conceive of anything bigger than the fullness of the Godhead - and it is ours, in Christ.
Secondly, in 17, there is a double contrast presented, between law and grace, Moses and Jesus, and between 'giver' and 'came'. Moses was distinct from the law; the law was given by him, but he was not the law. But grace and truth came by Jesus Christ because He is grace and truth. Westcott comments, 'The Law is represented as an addition to the essential scheme of redemption (cf Galatians 3:19; Romans 5:20). It was 'given' for a special purpose. On the other hand the Gospel 'came', as if, according to the orderly and due course of the divine plan, this was the natural issue of all that had gone before. Judaism was designed to meet special circumstances; Christianity satisfies man's essential nature.... The Gospel is spoken of as ‘grace’, so far as it is the revelation of God's free love, and as 'truth’, so far as it presents the reality and not the mere images and shadows of divine things.'
Finally, in 18, John justifies the claim of the gospel to be the Truth. The Christian revelation is an exclusive revelation. There is no other way of knowing God except through Jesus Christ. And this, John means, is what I am now going to write about.