What does Judges 3:11 mean?

God has empowered the first of what will be 12 named judges—deliverers, serving as military and civic leaders—in this book. God uses Othniel (Judges 3:9–10) to free Israel from eight years of suffering under the rule of a foreign king. God does this by placing the Spirit of the Lord on Othniel to empower him to do what would normally be impossible for one mere mortal man.

Now we're told that a time of rest followed this great victory. This is the pattern of the era of the judges: so long as the judge lived, the land continued to be protected (Judges 2:18). Othniel lived another 40 years after the struggle against Cushan-rishathaim, and the people of Israel had peace for those four decades. Forty years was often used as a way of saying "one generation." After Othniel died, however, the pattern repeated.