God causing the Israelites to defeat Jabin and his army is spoken of as is God himself defeated Jabin as the people of Israel watched. (See: [[rc://en/ta/man/translate/figs-metaphor]])
Here "him" refers to Jabin who represents himself and his army. AT: "they destroyed Jabin and his army" (See: [[rc://en/ta/man/translate/figs-synecdoche]])