Matthew Poole and continuators on Judges 15:20

20 And he judged Israel in the days of the Philistines twenty years.

i. e. He pleaded their Cause, and avenged them against the Philistinees.

i. e. Whilst the Philistines had the Power and Dominion, from which he was not fully to deliver, but onely to begin to deliver them, as it was foretold, Iudg. 13. 5. From this place it is manifest that in the computation of the times of the Judges, the years of Servitude or Oppression are not to be separated from the years of the Judges, and added to them, but are comprehended within them; which proposition is of great importance for clearing this difficult part of Scripture-Chronology, and for justifying that account of times given 1 King. 6. 1.