John’s gospel is vastly different from those of Matthew, Mark, and Luke, the synoptic gospels, or the gospels that are so much alike. Most of the accounts given by these three writers cover Jesus’ life in Galilee. John deals primarily with His life away from Galilee, with about the last five months of Jesus’ life, centering primarily on Judea and Jerusalem.
As far as we know, John’s gospel was written about A.D. 90 or after Jesus had ascended, after the gospel had begun its march across the earth. The world had seen the ministry of Peter, of Paul, and Luke, his traveling companion; and several missionary journeys had been made. John not only was an eyewitness from the beginning, one of the original twelve apostles who went through Jesus’ life with Him in His public ministry of about three years, but he was a man who lived through all of the spread of the gospel in most of the first century and was the one to look back upon it.
Study the Book of John to better understand the deeper teachings and deeper sufferings of Jesus, a book that is talking more to the believer, although it is for the whole world. You will begin to understand that John’s gospel is not so much about events but about Truth. The other gospel writers, Matthew, Mark, and Luke, wrote mostly about Jesus the person, the places He went to, the things He did. John does that to some extent, but mostly he is dealing with the eternal truths about the Son of God.