Judges 9:20
But if not, let fire come out from Abimelech, and devour the men of Shechem, and the house of Millo; and let fire come out from the men of Shechem, and from the house of Millo, and devour Abimelech.
Cross-references
Judges 9:15 is the bramble's threat in the parable — fire devouring cedars. Verse 20 applies that same fire imagery to Abimelech and Shechem.
Judges 9:23 shows God sending an evil spirit to cause discord — the direct means by which Jotham's curse of mutual destruction begins to be fulfilled.
Judges 9:56 states God returned Abimelech's evil upon him — summarizing the outcome of the curse in verse 20.
Judges 9:57 explicitly says the curse of Jotham came upon the men of Shechem — direct fulfillment of verse 20's curse.
Judges 9:49 shows Abimelech setting the tower of Shechem on fire, directly fulfilling the curse that fire from him would devour them.
Judges 9:53 records Abimelech's death by a millstone from a woman of Shechem, fulfilling the curse's other half—destruction from Shechem upon him.
Judges 7:22 recounts God turning Midianites against each other — same divine judgment strategy of internal conflict as in verse 20's curse.
2 Chronicles 20:23 tells of Ammon and Moab destroying each other — a direct parallel to the mutual fire of verse 20 between Abimelech and Shechem.
In Ezekiel 28:18, God brings fire out from within Tyre to consume it — nearly identical language to the fire from within in Judges 9:20.