But NWT Rbi8 says: "At that Jehovah let Eglon the king of Moab grow strong against Israel"
NWT 2013: "And once again the Israelites began doing what was bad in Jehovah’s eyes. So Jehovah let Egʹlon the king of Moʹab prevail over Israel, because they did what was bad in Jehovah’s eyes."
So "let" versus "strengthened" or "gave" as others render the Hebrew. Did Jehovah permit Eglon and other armies to dominate Israel or was his role a more active one?
Every commentator I read takes the view that Jehovah actively strengthened Eglon. K-D have this comment:
When the Israelites forsook the Lord again (in the place of וגו את־הרע ... ויּעשׂוּ, Judges 3:7, we have here the appropriate expression ... הרע הרע לעשׂות, they added to do, i.e., did again, evil, etc., as in Judges 4:1; Judges 10:6; Judges 13:1), the Lord made Eglon the king of the Moabites strong over Israel. על חזּק, to give a person strength to overcome or oppress another. כּי על, as in Deuteronomy 31:17, instead of the more usual אשׁר על (cf. Jeremiah 4:28; Malachi 2:14; Psalm 139:14).
In my estimation, Rotherham is good on this subject of "do" versus "let do."