That the cruelty done to the threescore and ten sons of Jerubbaal might come, and their blood be laid upon Abimelech their brother, which slew them; and upon the men of Shechem, which aided him in the killing of his brethren.
So that the harsh treatment towards the seventy sons of Jerubbaal would happen, and their blood would be on Abimelech, their brother, who killed them. This also includes the people of Shechem, who helped Abimelech in killing his brothers.