I noticed that in the 2011 NIV, Job 28 is marked off as an interlude as does not appear in quotation marks; whereas in the 1984 NIV, the text appears in quotation marks and is considered a part of Job's final speech. I can see how 29:1 might recommend the 2011 approach. Should this passage about wisdom be considered an interlude by the narrator? If so, why might the narrator choose to place it there?
Dr. Mayer Gruber, Associate Professor in the Department of Bible and Ancient Near Eastern Studies at Ben-Gurion University, wrote a very lengthy introduction to the Book of Job in the Jewish Publishing Society Jewish Study Bible, based on the JPS Tanakh. Without equivocation, he states, "Job is the most difficult book of the Bible to interpret."
Regarding the passage in question, he writes:
Because the two speeches in 27.2-28.28 are set apart from the rest of the book by the distinct formula at 27.1 and 29.1, "Job again took up his theme and said," and because the theology of these chapters is less radical than the theology fo the rest of the material attributed to Job, some scholars have concluded that 27.2-28.28 belongs to a composition distinct from the symposium in 3.1-26.4. In this speech Job refuses to blaspheme God (27.2-6), and he affirms that in the end justice prevails (27.7-23). Then in 28.28, echoing Psalm 111.10 and Proverbs 1.7; 9.10, Job states that true wisdom consists of Job's own twin virtues, fearing the Lord and shunning evil (cf. Job 1.1,8; 2.3). This speech therefore would originally have served as a response to Eliphaz, Bildad, and Zophar who, like Job's wife in 2.9, urged Job to respond to his suffering by cursing God and dying. In this reading the speech of Job in chs 27-28 was followed originally by a divine promise (which has been lost) to reward his steadfastness; this was followed, in turn, by 42.7-17 (the current prose epilogue), in which Job is rewarded for what he has said in chs 27-28 and the friends are castigated for having encouraged Job to blashpheme God. The other solutions to the dilemma of chs 27-28 involved reassigning most of 27.7-23 to Zophar (thereby completing the third cycle) and treating ch 28 as an independent Hymn to Wisdom composed by the author of the book of Job.
Professor Gruber indicates, however, that he does not support the "Hymn of Wisdom" interpretation. Elsewhere he explains,
Most modern scholars try to reconstruct a lost speech of Zophar from parts of ch 27. But to do so is to ignore the editors' designation of Job 27.1-29.1 as a separate block of text introduced by the peculiar formula, "Job again took up his theme ..."
If this is a separate block of material, we must assume either that the absence of Zophar's third speech is intentional or that the speech was lost and no remnants of it are to be found in the extant book.
I think I confused myself trying to follow Prof. Gruber, but his opinion seems to be that Job 28 should NOT be considered an interlude, but, rather treated as a continuation of Job 27. He qualifies his opinion, however, by stating that there are other interpretations. It seems that the NIV editors changed their opinion over time about which interpretation to adopt.
My Jerusalem Bible interprets Job's speech in chapter 27 as ending at verse 12. It assigns the rest of chapter 27 to Zophar (via the paragraph heading "The speech of Zophar: the accursed"). When it gets to chapter 28 it makes a major break with a chapter heading that says "D. A HYMN IN PRAISE OF WISDOM" and follows this with the paragraph heading "Wisdom is beyond man's reach". The entire chapter is set as three stanzas of verse. The end of the chapter has another major break and the chapter heading "E. CONCLUSION OF THE DIALOGUE" introducing chapter 29.
The Jerusalem Bible, then, does not attempt to assign chapter 28 to any of the characters making speeches in Job. It breaks chapter 27 after verse 12 based upon a change of subject and tone from Job's defensiveness to accusative content. It assigns the accusative content to Zophar because Job's other two accusers have already had their say in this round of the conversation.