“Although the author’s name does not appear in the Gospel, early church tradition strongly and consistently identified him as the apostle John. The early church father Irenaeus
(A.D. 130- 200) was a disciple of Polycarp (A.D 70-160). (Polycarp was a disciple of the Apostle John. With Polycarp’s permission, Irenaeus testified) that John wrote the Gospel during his residence at Ephesus in Asia Minor when he was advanced in age” (John MacArthur).
The author preferred to identify himself as the disciple whom Jesus loved (read John 13:23; 19:26; 20:2; 21:7 & 20). After six days, Jesus took with him Peter, James, and John his brother, and brought them up into a high mountain by themselves (Matthew 17:1). The three disciples must have been the closest friends of Jesus.
The Gospel of John has been called “the crown of the Scriptures.” It is perhaps the easiest book to read in the New Testament. At the same time, it is the most knowledgeable intellectual book.
The eagle is a fitting symbol for the book of John. William Barclay says, “the eagle of all
living creatures alone can look straight into the sun and not be dazzled.” The Apostle John of all the New Testament writers has the most penetrating gaze into the eternal mysteries and the eternal truths, and into the very mind of God.
The central theme of the Gospel of John is written in John 20:31. The author says, “but these are written, that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in his name.”