After a few years of debating chiasmus here are some suggestions to discern a pattern that is meaningful and not imagination.
- The section of scripture is defined by repetition of key words/phrases i.e. bracketed or book-ended.
- The pattern is characterised by repetition of keywords, and phrases or by opposites (chiasmus based only on concept rather than exact repetitions are more difficult to agree on).
- if key phrases are inverted (“heaven and earth” v “earth and heaven”) this is strong evidence.
- The chiasm has a balanced symmetrical shape.
- The centre – often a regular parallelism – is highly significant.
- the whole unit makes sense.
- the unit respects other textual features.
- Broken patterns may nonetheless be significant.