The rest of this phrase can be understood from what Jotham said in verse 19. Alternate translation: "But if you did not act with honesty and integrity with Jerub Baal and his house" (See: [[rc://en/ta/man/jit/figs-ellipsis]])
Jotham is speaking a curse. He speaks of Abimelech destroying the people of Shechem as if he would burn them with fire. (See: [[rc://en/ta/man/jit/figs-metaphor]])
Jotham is speaking a curse. He speaks of the people of Shechem and Beth Millo destroying Abimelech as if they would burn him with fire. (See: [[rc://en/ta/man/jit/figs-metaphor]])