Theme and Literary Context
Although some see the book as repeated themes organized in several spirals, here we treat the book in five sections:
The first section (1:1-4) addresses the very foundation of Christian faith: first, Christ is both totally God and totally a man (1:1); second, such a truth is now revealed to all human (1:2); third, it provides and is the only ground for all believers to have fellowship with Christ and with each other (1:3); and fourth, this is the key to fulfill God’s commandments and the purpose of a Christian life in complete joy (1:4). The first section serves as a kernel for the entire book. According to MacArthur
