A chiasm is a literary structure where vocabulary of the first section of a passage is repeated in the second. The center of the chiasm is typically the climax of the passage. In Luke 10:17b-20 the center and climax is where Jesus says to the seventy, “Behold, I have given you authority to tread on serpents and scorpions, and over all the power of the enemy, and nothing will injure you” (Luke 10:19).