Why preach through the book of John?
1) It is the word of God. Preaching through a book will protect those who teach from simply focusing on their favorite topics, or even on fallible judgments about what we think the people need on any given Sunday.
2) There is a dedication to portraying the glory of Jesus throughout the book. Even starting with the first verse. We desire our church to be infatuated with the glory of Jesus. “The Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father” (John 1:14).
3) John is an unparalleled combination of simple storytelling and profound doctrine. As a church, we must be characterized by evangelistic effectiveness and doctrinal depth. One without the other could make us ineffective in our missional efforts.
4) John was written by one who had a very close relationship to Jesus. He was “the disciple whom Jesus loved” (13:23; 20:2, 21:7, 20). We desire our church to be close to Jesus. John gives us a first hand look at that experience.
5) Finally, we want our church to desire Christ above all. A theologian named John Owen said, "The revelation of Christ deserves the severest of our thoughts, the best of our meditations and our utmost diligence in them. What better preparation can there be for our future enjoyment of the glory of Christ than in a constant previous contemplation of that glory in the revelation that is made in the Gospel." How better can we be made useful for the world, or ready for heaven, than to give our “best meditations and our utmost diligence” to the revelation of the glory of Christ?