The apostle John continues to unravel the great truths of God's incarnation in Jesus Christ in these first verses of chapter 1--we are introduced to the forerunner--John the Baptist--and his witness to the light. The great truth unpacked to us in verse 16 and 17 is that of Jesus' perfect combination of grace and truth! The law revealed our sin perfectly, but could do nothing to change us. God's grace changes us!