What was John's role?

John the Evangelist likely aims to present John the Baptist as announcing the fulfilment of passages like Isaiah 8:20–9:2. In this scripture, “gloom of anguish” and “thick darkness” (Isa. 8:22) symbolise the curse of the covenant and exile from the land, while “dawn” (Isa. 8:20), which makes “glorious the way of the sea” (Isa. 9:1), and “great light” (Isa. 9:2) all symbolise what God will accomplish for his people during the new exodus and their return from exile. 

The light to which the Baptist testifies is, therefore, the hope of Israel for the glorious eschatological restoration God promised his people through the prophets. John bears witness to the light—how Jesus will bring the dawn of salvation—“that all might believe through him” (John 1:7). John testifies to the fulfilment of the Old Testament promises in Jesus, and the response he seeks from his testimony is belief—faith.

To prevent anyone from being distracted by the extraordinary stature of the prophet sent from God or the God-given clarity and power in which he ministers, John states that the Baptist relates to Jesus in the same way the moon relates to the sun: “He was not the light, but came to bear witness about the light” (v. 8).

 The renewal of prophecy in John’s ministry, apparently dormant since Malachi, is not the main focus. The focal point is the light to whom the prophet points: Jesus.

We must consider John 1:9, “The true light, which gives light to everyone, was coming into the world,” in its immediate and broader contexts. In the immediate context, Jesus is undoubtedly the true light (1:4–5, 7). In the broader context, we understand how Jesus “gives light to everyone” in 3:19–21 and other verses, such as 8:12, where Jesus declares that he is the “light of the world.”