If we do not understand the purpose for an object, an object can be useless for us. If we do not know the purpose for a book of the Bible, it will not be nearly as useful for us to bring about the purposes of God in our lives. Paul wrote Romans to prepare the way for him to preach the Gospel both to the church in Rome and the unreached peoples of Spain. We are reminded that the Gospel is integral to the life of the church and the mission of the church to reach the lost.