en_tn/jdg/09/23.md

God sent an evil spirit between Abimelech and the leaders of Shechem

This means that God applied the curse Jotham made by sending an evil spirit to cause trouble and animosity between Abimelech and the leaders of Shechem.

God did this so the violence done ... helped him murder his brothers

The passive phrases can be stated in active form. Alternate translation: "God did this to avenge the seventy sons whom Abimelech their brother murdered and the men of Shechem helped murder" (See: rc://en/ta/man/translate/figs-activepassive)