recorded in this book. But these are written 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 20:30–31). Here John presents us with a key by which we can understand the aim and shape of his book.1 In the epistles, the key is often contained in the opening verses of greeting, as in Titus 1:1, Paul, a servant of God and an apostle of Jesus Christ for the faith of God’s elect and the knowledge of the truth that leads to godliness.