Discussion is beginning on determining the criteria we should apply in recognising chiasmus in scripture. I have found J T Walsh’s book “Style and Structure in Biblical Hebrew Narrative”. 2001, the Liturgical Press, Minnesota, helpful is exposing types of repetition. Here are some quotes.
“Repetition is the most common formal device for organising a literary unit in biblical Hebrew prose. Repetition, of course, can serve many literary functions in a prose text: repeated words or themes (e.g., keywords or leitmotifs) can unify a passage, create emphasis, or delay action and create suspense. In none of these cases, however, does the repetition necessarily provide the passage with an overall structure” (p 7).
” One variation of symmetry deserves particular mention. Hebrew narrative will sometimes violate an otherwise symmetrical pattern with an insertion, deletion, or other disturbance of the patterned regularity. The clearer the fundamental symmetry and the more obtrusive the disturbance, the more the asymmetrical element draws a reader’s attention. This gives asymmetry great potential as a literary tool” (p 8).
Note: two things I take from this:- we need to be careful not to confuse repetition with structure, and we need to be careful not to shoehorn every verse into a neat pattern and thereby miss intended asymmetry. See James 2:17-26 as an example of asymmetry that makes a great point.