Perhaps the first book written down in the New Testament era, the book of James is written to what appear to be synagogues worshiping much like the Jews had ever since coming back from Babylonian exile. Now once again scattered by the likes of Saul of Tarsus, the letter is penned as a general letter to be copied and spread throughout the scattered Jewish Christian community.
The message of the epistle can be best described as a call to sincere adherence to the Law as taught by Jesus. This meant that the poor and underprivileged among the congregation must be cared for. Hypocrisy was to be confronted and condemned. Just believing in God was not enough in the eyes of fellow Christians — or in God's eyes.
James's book is written as a letter.