“John” is thought of as the gospel of love because of the many times it is mentioned. It was written near the end of the first century, after the writer and other Christians of that time had time to ponder the teachings of the other evangelists, and for John to develop his own theology. It is more theological than the other Gospels which are called the “synoptic” gospels, because of their similarity, and the way they see the life and teachings of Jesus in a more “earthly” way. If you keep this in mind it will help you better understand where John is coming from.