Chiastic
From Conservapedia
A chiastic literary structure presents themes or characters in a symmetrical pattern, resembling the Greek letter "chi" (X) or (A-B-C-C'-B'-A'). This can make it easier to remember.
President John F. Kennedy's famous line from his Inaugural address was chiastic: "Ask not what your country can do for you, ask what you can do for your country." Indeed, it was easy to remember and repeat.
The Book of Leviticus in the Bible is structured chiastically.
