In order to understand the importance of knowing the truth about Jesus (Christology) it is first necessary to remember the true nature of Christianity itself. The latter is not a lifestyle, a moral code, a system of religious rituals, or a corpus of shared beliefs. Christianity is very simply a dynamic relationship with a Person, the Lord Jesus Christ:
“Christianity is a relation to a person. It is not essentially an idea or institution. It has defined itself in canon and tradition as a relation to Christ. He is the one to whom faith relates and in whom faith trusts. Gustavo Gutierrez writes: ‘Being a Christian does not mean, first and foremost, believing a message. It means believing in a person.’ Christian teaching is therefore personally grounded. It lives in response to a personal life yet alive. Christian teaching only serves to show the way that leads to faith in this person.” (Thomas Oden*)
Although many words, deeds, and common interests will characterize this relating, these things are not the defining features of Christianity. We may legitimately refer to Christian beliefs, Christian behavior, and Christian fellowship but to be a Christian is to be in a living, vital relationship with Jesus. Evangelicalism popularized the question, “do you have a personal relationship with Jesus Christ?” This is positive for how it underscores the centrality of the truth in view, yet perilous because it lends itself to becoming trite. Everything about authentic Christianity is profoundly relational, but it is not just another “relationship” like we are accustomed to.
Surely, and beautifully, we are beckoned to relate to Jesus in love and friendship. Yet this relating also includes trembling before our Judge, bowing before our Creator, obeying our King, praising our Savior, and worshiping our God. He is a Person and not a concept, so the entire Christian life is one of relationship. Yet this Person is unlike any other, and therefore the relationship is altogether unique as well.
When it is recognized that all relationship, including this one, finds both its foundation and its growth in knowledge, the necessity of Christology becomes clear. Christology is not a subject among other doctrines of the Christian faith. It is everything. Christianity is a relationship to a Person, relationship is sustained through the fostering of adoring knowledge, and thus Christology is virtually synonymous with Christianity. The depth and accuracy of our knowledge will consequently determine whether we relate to Jesus rightly.
No one is to be exempt from this consuming obsession with knowing Him. If the church were students, we would all have one major and then many different minors. Minors are wonderful things. Problems arise only when minors begins to usurp the attention due our Major, who is our Master and our Maker.
(*quote taken from Thomas Oden, Systematic Theology Volume II: The Word of Life (Peabody, Massachusetts: Hendrickson Publishing Inc, 2006), p 2-3.)