וְאָבִ֨יו וְאִמּ֜וֹ לֹ֣א יָדְע֗וּ כִּ֤י מֵיְהוָה֙ הִ֔יא כִּי־תֹאֲנָ֥ה הֽוּא־מְבַקֵּ֖שׁ מִפְּלִשְׁתִּ֑ים וּבָעֵ֣ת הַהִ֔יא פְּלִשְׁתִּ֖ים מֹשְׁלִ֥ים בְּיִשְׂרָאֵֽל׃ (פ)
But his father and his mother knew not that it was of the LORD; for he sought an occasion against the Philistines. Now at that time the Philistines had rule over Israel.
Rashi on Judges
As He sought a pretext. An accusation with which to provoke a confrontation against them.