The book of Job is very unique among all the books of the Bible. It relates human suffering, especially undeserved suffering, to divine justice. Job confronts one of the greatest mysteries of unmerited pain and misery not caused by wrong doing. Retributions of wrong doing are not always as obvious as the theology of Jobs friends.
Though this type of writing was well established in the OT world, none of the other books write so eloquently and fully on the subject as this book does. Job is generally classified as wisdom literature, but unlike the other books of wisdom literature which describe the subject matter rather than the form, the book of Job used poetry of many forms such as lament, oracles, wisdom, proverbs, irony, and hymns. This book stands outside of regular forms of classical Hebrew because of it’s grammar, syntax, and orthography. Nonetheless, and contrary to popular belief as is with most books of poetical literature, this book is also historical. And most importantly that it too is inspired of God . Henry states further about the Jews preserving the Word of God as historical:
The Jews, though no friends to Job, because he was a stranger to the commonwealth of Israel, yet, as faithful conservators of the oracles of God committed to them, always retained this book in their sacred canon. The history is referred to by one apostle (James 5:11) and one passage (ch. 5:13) is quoted by another apostle, with the usual form of quoting scripture, It is written, 1 Co. 3:19.1
Henry, Matthew. 1991. Matthew Henry’s Commentary on the Whole Bible, Complete and Unabridged in One Volume. Peabody, Massachusetts. Pg. 521.
So the dialogues are poetical, and many categorize it as a romance, but another important point of it’s historicity is given by the prophet Ezekiel who names him along with Noah and Daniel (Eze. 14:14).
Because of the incredibly numerous and contrasting resources available on who the author of Job was and a date as to when it was written, it is impossible to know who wrote the book of Job, at least within the constraints of this assigned task, or without divine intervention, so the most generally accepted findings are brought into light. It seems Job lived in the second millennium and shared a tradition as a Hebrew patriarch. Smick comments in support of this:
Job’s longevity of 140 years, his position as a man whose wealth was measured in cattle and who acted as priest for his family, and the picture of roving Sabean and Chaldean tribesmen fit the second millennium better than the first.
Smick, Elmer B. 1998. The Expositors Bible Commentary. Grand Rapids, Michigan. Pg. 843.
Job however probably lived approximately 200 years since this corresponds closely to the age of the patriarchs and more importantly, the 140 years was after his calamities and being restored back to health.
When the book was written requires an even more complex answer. It does seem that it went through some kind of literary development. The book may not have reached it’s final form until the first millennium. There are several other ancient near East parallels very similar to the biblical book of Job from Mesopotamia (2nd millennium), the Babylon Theodicy (1100 B.C.), texts from the Egyptian Twelfth Dynasty, a text from Ugarit, among others. However Crenshaw describes how the Biblical book of Job stands alone:
None of these texts provides an exact parallel to the book of Job, which adapts the traditional genre of debate and framing narrative from the Babylonian Theodicy and I Will Praise the Lord of Wisdom respectively, adding more friends and enhancing the theophany by incorporating it into the debate. In addition, the biblical author uses extensive catalogues, or lists, hymnic texts, a negative confession, and laments. In the end, the book of Job stands alone, like the hero of the book.
Crenshaw, James L. 2001 The Oxford Bible Commentary. Oxford, New York. Pg. 332-333.
Though Crenshaw correctly states some of the uniqueness of this book, as noted elsewhere above, he seems to agree with popular modern belief that the book is an adaptation of literature and not historical which is not the argument being made here.
To briefly summarize, the book of Job opens with a prologue stating Jobs current status and his testing by Satan. Then begins three cycles of dialogue and disputes between Job and his friends. After Jobs closing discourse, there begins an interlude on wisdom. Job then begins with a monologue which is followed by a speech from a previously unknown friend. Near the end, God then intervenes with a discourse in which Job may respond, and then God gives a second discourse. In the epilogue, the author finishes with God’s verdict and Job is restored.
Biblical Studies 