What is the center of the Bible? What is the central teaching of the Scriptures? If you boiled down the Bible to its most basic teaching, what would that teaching be? In other words, what is the point and essence of Christianity?
Some say that the central teaching of the Bible is this: "Be nice to others," or something along those lines. But people who say this apparently have not read the Bible, or at least not read it carefully. The Bible itself tells us why the Bible was written! It tell us the main and central teaching of the Scriptures: "These things are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in His name" (John 20:31). In other words, the center of the Bible is Jesus Christ, the Son of God. Jesus Himself says it: "You search the Scriptures because you think that in them you have eternal life, and it is they [the Scriptures] that bear witness about me" (John 5:39). Even more, remember when Jesus appeared to the disciples on the road to Emmaus? What did Jesus say? "'Was it not necessary that the Christ should suffer these things and enter into His glory?' And beginning with Moses and all the Prophets, He interpreted to them in all the Scriptures the things concerning Himself" (Luke 24:26-27).
Scripture clearly teaches that the central teaching of the Scriptures is Jesus: Jesus is the Christ, the Son of God, who was delivered up for our sins, to win eternal life for those who believe.
This means that the central teaching of Scripture is not "be nice to others," or to "love one another," or anything in that vein. This also means that the Bible is not a "how-to-manual." The Bible is not an acronym that stands for "Basic Instructions Before Leaving Earth" (B.I.B.L.E.). All of these attempts miss the mark. The center of the Bible is about Christ crucified for sinners. The Old Testament is about Jesus (John 5:39; Luke 24:26-27). The New Testament is about Jesus (John 20:31; 1 John 5:13). Christ explained that everything written in the Scriptures was about His suffering, death, and resurrection, and that the goal of this all was your repentance and forgiveness, for all people (Luke 24:44-47).
This is why any attempt to define the main objective of the Bible as a guidebook for how to live is not only wrong, it is false doctrine. To say that the center of the Bible is about being nice to others is idolatrous. Why? It elevates your works above God's. It puts what you're supposed to do above what God has actually done for you! It replaces Christ, the center of the Bible, with something else: Moralism. The purpose of God's Word, the very goal of the Christian faith, is not to teach you how to be a good man, a nice person, a kind human-being. The goal of the Scriptures is for you to repent of your sin, and to find the forgiveness of all of your sins in Christ's death on the cross. Your salvation does not depend upon your works—It depends upon Jesus' death and resurrection. God gives you eternal life freely through the self-donation of Christ on the cross.
So, if you hear someone say that the purpose of Christianity and the Bible is to be a good person, then you should immediately and sharply correct them. Tell them that the purpose of every other religion in the world is to be a good person and earn your way into heaven. But the purpose of the true religion, the purpose of Christianity is that you confess your sin and unworthiness, and that you receive the forgiveness of sins that Christ has freely won for us on the cross. This is the dead center of the Bible: Christ for you. And do everything to not fall into thinking that Christianity is just some set of moral codes. It is not. It is more than that: It is about God lovingly, graciously condescending Himself to us in this earth, bearing our sin and our guilt, and suffering on the cross so that we might live forever. Don't deviate from the center of the Bible. Put this on the forefront of your mind. Rest your faith on Christ alone.