The Gospel of John declares its purpose clearly--"these are written that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name." Thus it fulfills a dual function, encouraging believers and providing them with evidences for proclaiming that Jesus is God's Messiah, the divine, incarnate Son of God.
Christians today, as in the first century, can draw strength and courage from John's telling of the story of Jesus, a telling that consistently reflects not only the words and deeds of Jesus but their inner significance. We are called to worship as we find the Father, Son and Spirit revealed in the Gospel. And as in Jesus we discover God's light, life and love, we learn to respond in faith, humility and obedience.
Throughout, Whitacre explains what the gospel meant to its original hearers and its application for us today.