New Defender's Study Bible Notes
3:8 Chushan-rishathaim. This name is actually an epithet–“doubly wicked Chushan.” There is some evidence that he may actually have been a Horite (or Hurrian) king in northern Syria who had conquered portions of Mesopotamia, and so considered himself king of Mesopotamia.
3:11 And Othniel. Othniel had previously distinguished himself as conqueror of Debir (Joshua 15:15-17), and so was able to become Israel’s first judge, leading them to repentance and victorious freedom after their first subjugation since the days of their fathers in Egypt.
3:14 eighteen years. The listed periods of servitude in the book of Judges total 111 years, and included times of subjection to no less than nine different nations. Israel’s periods of apostasy were costly.
3:15 A man lefthanded. Ehud, the second judge is the only left-handed man mentioned by name in the Bible (but see Judges 20:16). This fact is apparently mentioned here because it helped him catch the king of Moab off guard.
3:31 Shamgar. This very brief mention of Shamgar (noted also in Judges 5:6), together with the notation of Ehud’s death in the next verse, may suggest that Shamgar’s rule near Philistia was contemporaneous with Ehud’s rule farther east.