Just as each limb, appendage, and organ has a specific purpose in the body, each book in the Bible has a specific purpose too. Such is the case when we focus our attention upon the Gospels. For example, the purpose of the book of Matthew was to portray Jesus as the son of David, the Messiah, and the King of the Jews. It is directed especially toward a Jewish audience. The genealogy traces the Lord's family tree from Mary back to Abraham. The key word of Matthew is "fulfilled" because the Messianic prophecies were fulfilled in Jesus Christ.
The Gospel of Mark portrays the Lord as the Suffering Servant with the Roman reader especially in mind. It opens with the beginning of the public ministry of Christ and records events of His life. The key word is "straightway," which indicates immediate action.
The Gospel of Luke portrays Christ as the Son of Man and emphasizes the humanity of Christ. It traces the genealogy of the Lord back to Adam and has the Greek or Gentile reader in mind. The first three Gospel books describe events in the life of the Lord Jesus Christ.
When we come to the Gospel of John, we find that he emphasizes the meanings of the events in the Gospels. He records much of what is still unsaid. John portrays Jesus Christ as the Son of God, tracing Him back not to Abraham or Adam, but before time. In fact, John is called the Genesis of the New Testament. There is no genealogy, manger scene, boyhood, baptism, temptation, Mount of Transfiguration, or Gethsemane in the book of John. There are no lepers, publicans, demoniacs or parables. The Gospel of John was written with the Church in mind.
The Gospel of John is a great book for new Christians to read and study. The language of the book is simple, and the vocabulary is small. Six hundred words from John's vocabulary were used in this book. This is equivalent to the mind of a child seven years of age. Do you know the popular words found in John? Here are some of them.
Dr. S.D. Gordon stated that there are three keys that unlock the Gospel of John.
1. The Back Door Key-
John 20:30-31... And many other signs truly did Jesus in the presence of his disciples, which are not written in this book:  But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.
These verses unlock the book and state the purpose of the Gospel of John.
2. The Side Door Key-
John 16:28—I came forth from the Father, and am come into the world: again, I leave the world, and go to the Father.
This took place at the Last Supper. Jesus use to be with the Father and would return to Him after completing His Father's will.
3. The Front Door Key-
John 1:11-12... He came unto his own, and his own received him not.  But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:
This key is at the front of the book, down low within a child's reach. This key opens wide the book.
If you are going to fully understand the book of John or any other book in the Bible, you need to know the Lord Jesus Christ as your personal Savior and believe that He is the Son of God. Those who do not know the Lord lack spiritual discernment.
1 Corinthians 2:14—But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.
The Holy Spirit gives the Christian understanding of God's truth. He indwells the believer when he puts his faith in Christ.
1 Corinthians 2:13—Which things also we speak, not in the words which man's wisdom teacheth, but which the Holy Ghost teacheth; comparing spiritual things with spiritual.
John 14:26—But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.
The Holy Spirit teaches that Christ is the Son of God. This is what John was trying to show us in each chapter of this book. Christ is everything to all men because He is God! Notice how He is portrayed in each chapter of this book.
The Portrayal of Christ in the Gospel of John
Why does it matter that Jesus is God? It matters because we can know the truth about God and what the Lord is like. Apart from Christ, you and I cannot know what God is really like and understand the doctrinal truths of the Bible. To know Christ is to know God the Father. Philip could not understand this truth.
John 14:8-9—... Philip saith unto him, Lord, shew us the Father, and it sufficeth us.  Jesus saith unto him, Have I been so long time with you, and yet hast thou not known me, Philip? he that hath seen me hath seen the Father; and how sayest thou then, Shew us the Father?
What Jesus did for us is open a window of time that we might see the eternal, unchanging love of God Almighty. God hates sin, but He loves the sinner. There must be atonement for sin. In Christ, we have that atonement.
The fact that Jesus is God makes His death on the cross very significant. He was the one acceptable sacrifice for sin and is able to satisfy all of our needs.
Ephesians 3:18-19... May be able to comprehend with all saints what is the breadth, and length, and depth, and height;  And to know the love of Christ, which passeth knowledge, that ye might be filled with all the fulness of God.
James Montgomery Boice shared a true story concerning the truth of these verses and the dimensions of the love of God. During the Napoleonic period in Europe, some of Napoleon's soldiers opened a prison that had been used in the Spanish Inquisition. There were many dark dungeons in that prison, but in one of the cells the soldiers found something that was particularly interesting. They found the small remains of a prisoner, his flesh and clothing were long gone, but there was one ankle bone that remained in a shackle. It was the message that was carved on the wall that spoke volumes. Using a sharp piece of metal, the prisoner carved into stone a crude cross. Inscribed around the cross were the Spanish words for the four dimensions mentioned in Ephesians 3:18: height, depth, breadth, and length. As this prisoner was dying in his chains, his heart, mind, and soul were free from the chains of despair. He found comfort, grace, love, strength and satisfaction in the love of Christ that satisfied him wholly. The truth of God's Word and the comfort of the Holy Spirit were anchors to his soul.
Why is the humanity of Jesus Christ important? There are several reasons.
1. First of all, it makes it possible for the Lord to die.
Hebrews 10:4-7... For it is not possible that the blood of bulls and of goats should take away sins.  Wherefore when he cometh into the world, he saith, Sacrifice and offering thou wouldest not, but a body hast thou prepared me:  In burnt offerings and sacrifices for sin thou hast had no pleasure.  Then said I, Lo, I come (in the volume of the book it is written of me,) to do thy will, O God.
2. It enables the Lord to understand what men go through: weariness, disappointment, misunderstanding, rejection, false accusations, sorrow, pain, and betrayal.
Hebrews 4:15-16... For we have not an high priest which cannot be touched with the feeling of our infirmities; but was in all points tempted like as we are, yet without sin.  Let us therefore come boldly unto the throne of grace, that we may obtain mercy, and find grace to help in time of need.
3. It qualifies the Lord to be a mediator that can represent both God and men.
1 Timothy 2:5—For there is one God, and one mediator between God and men, the man Christ Jesus;
4. It provides us with an example on how to live a life that is pleasing to God.
1 Peter 2:21—For even hereunto were ye called: because Christ also suffered for us, leaving us an example, that ye should follow his steps:
The word "example" comes from the Greek word hupogrammos. This word was used to describe how children were taught in Bible times. A hupogrammos was an outline sketch of a letter that the students filled in or traced in their writing exercise tablets. The child traced or copied the letters on lines below the sample letter or the hupogrammos. Christ is our pattern for living that we are to follow.
5. The humanity of Christ gave us hope and it gave value to our lives. It is interesting to note that where Christ is rejected, life is considered cheap and men's hearts tend to be hard, cold, and unfeeling.
Matthew 24:12—And because iniquity shall abound, the love of many shall wax cold.
In the Gospel of John, John ties the humanity of Christ with His deity in John 1:1-2.
John 1:1-2... In the beginning was the Word, and the Word was with God, and the Word was God.  The same was in the beginning with God.
In the beginning of what? Jesus existed from the beginning because He was God. The word "beginning" refers to when creation came into existence, not when Christ came into existence because He always existed. He never came into being because He has always "been." The word "beginning" is when "time" began. It does not refer to eternity, because eternity cannot be measured by time. Time is only a small portion of eternity because what we know of as eternity has no beginning and it has no ending. Jesus did not come into being when time began at the creation of the universe, because Christ is eternal. Christ existed before the creation of the world.
The term "word" is a reference to Jesus Christ. There are two words we want to direct our focus upon. They are the words "was" and "word." Notice the phrases, "was the word," "was with God," and "was God." Was Two Greek words are translated "was."
John 1:3 -All things were made by him; and without him was not any thing made that was made.
The word "was" is in the imperfect tense which indicates something is "on-going or is a mode of existence that transcends time. It indicates continued action in past time." Christ the Word belongs to a realm where time does not matter. The imperfect tense emphasizes continuous existence. In this case, it emphasizes the eternal existence of Christ. Jesus existed continuously before the occurrence of "the beginning." He had no beginning.
Colossians 1:17 —And he is before all things, and by him all things consist.
John 17:5—And now, O Father, glorify thou me with thine own self with the glory which I had with thee before the world was.
Micah 5:2—But thou, Bethlehem Ephratah, though thou be little among the thousands of Judah, yet out of thee shall he come forth unto me that is to be ruler in Israel; whose goings forth have been from of old, from everlasting.
The phrase "in the beginning" jogs the memory of another verse in the Bible that uses this same phrase. Moses used this same phrase in Genesis 1:1—. When you compare the way that Moses and John approach the beginning, you will find that the two men go in two different directions from the beginning. Moses follows "in the beginning" with the events that happened after the beginning (God created the heavens and the earth). John follows "in the beginning" with what happened before the beginning, Jesus "was." He existed before the beginning.
The "Word" comes from the Greek word logos. John used a Greek word that would appeal and be understood by both Jews and Greeks. To the Jews, a word was more than a sound. It did something because it was alive and was a unit of energy charged with power. The Hebrew language uses different words sparingly with only about ten thousand words. The Greek language is more precise with a vocabulary of 200,000 words. A word was something that was concrete such as an event or deed. What happens when God speaks? The answer is the event is done.
Genesis 1:3—And God said, Let there be light: and there was light.
Isaiah 55:11—So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it.
To the Greek people, the "word" was the mind of God and it was responsible for the majestic order of the world. The mind of God dwelling within a man, makes him a thinking, rational being. The divine "word" controls the world and mankind. John was saying, "The mind of God has come to earth in the person of Jesus Christ." Christ was alive and charged with power because He was God.
The Lord Jesus Christ is God's expression of communication. He is God's alphabet. He spells out "deity." Notice what John said in Revelation chapter one.
Revelation 1:8—I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty.
Christ is the Alpha and Omega or the A to Z of the alphabet. He is the Word and revealed from A to Z all that God is and what He is like.
Through Christ the mystery about God is unveiled. Jesus gives understanding to the confusing, secret, and mysterious matters about God. To the Jews, to call Christ the Word would be blasphemy. To the Greeks, that God was made flesh would be unthinkable. To John, it was good news for the human race.
John says, "The Word was WITH God." There are several prepositions in the New Testament that mean "with." This preposition is an especially strong one. It is the word pros, which suggests "close proximity" or "in company with." It also means "toward." All this adds up to the concept that the Word, the Lord Jesus Christ, was eternally in face-to-face fellowship with God and was in close company with God the Father. Jesus was not only near God the Father, He was in living communion with Him. They had intimate fellowship with each other.
John 10:30—I and my Father are one.
John 14:10-11—... Believest thou not that I am in the Father, and the Father in me? the words that I speak unto you I speak not of myself: but the Father that dwelleth in me, he doeth the works.  Believe me that I am in the Father, and the Father in me: or else believe me for the very works' sake.
We do not need to possess a faith; we need a faith that possesses us.