Question: "What is a chiasm / chiastic structure in the Bible?"
Answer: A chiasm (also called a chiasmus) is a literary device in which a sequence of ideas is presented and then repeated in reverse order. The result is a “mirror” effect as the ideas are “reflected” back in a passage. Each idea is connected to its “reflection” by a repeated word, often in a related form. The term chiasm comes from the Greek letter chi, which looks like our letter X. Chiastic pattern is also called “ring structure.”
The structure of a chiasm is usually expressed through a series of letters, each letter representing a new idea. For example, the structure ABBA refers to two ideas (A and B) repeated in reverse order (B and A). Often, a chiasm includes another idea in the middle of the repetition: ABXBA. In this structure, the two ideas (A and B) are repeated in reverse order, but a third idea is inserted before the repetition (X). By virtue of its position, the insertion is emphasized.
Some chiasms are quite simple. The common saying “When the going gets tough, the tough get going” is chiastic. The words going and tough are repeated, in reverse order, in the second half of the sentence. The structure is ABBA. Another example of a chiasm, also with the ABBA structure, is Benjamin Franklin’s axiom “By failing to prepare, you are preparing to fail.” Other chiasms are more complex, even spanning entire poems.
Many passages in the Bible exhibit chiastic structure. For example, Jesus’ words in Mark 2:27 are in the form of a chiasm: “The Sabbath was made for man, not man for the Sabbath.” Using the ABBA form, the words Sabbath and man are repeated in reverse order. Matthew 23:12 is another example.
A longer chiasm is found in Joel 3:17–21. This one has seven parts, diagrammed this way: ABCXCBA. Here is the passage:
“‘Then you will know that I, the Lord your God,
dwell in Zion, my holy hill.
Jerusalem will be holy;
never again will foreigners invade her.
In that day the mountains will drip new wine,
and the hills will flow with milk;
all the ravines of Judah will run with water.
A fountain will flow out of the Lord’s house
and will water the valley of acacias.
But Egypt will be desolate,
Edom a desert waste,
because of violence done to the people of Judah,
in whose land they shed innocent blood.
Judah will be inhabited forever
and Jerusalem through all generations.
Shall I leave their innocent blood unavenged?
No, I will not.’
The Lord dwells in Zion!”
The ideas presented in this prophecy follow this arrangement:
A - God dwells in Zion (verse 17a)
B - Jerusalem is holy (verse 17b)
C - Foreign invaders are banished (verse 17c)
X - The blessings of the Kingdom (verse 18)
C - Foreign enemies are destroyed (verse 19)
B - Jerusalem and Judah are preserved (verses 20–21a)
A - God dwells in Zion (verse 21b)
Other passages that provide examples of chiasms include Ecclesiastes 11:3—12:2; Genesis 6—9; Amos 5:4–6a; Isaiah 1:21–26; and Joshua 1:5–9. Chiastic patterns in the Bible are just one more example of the richness and complexity of God’s inspired Word.