תְּבַקְשֵׁם֙ וְלֹ֣א תִמְצָאֵ֔ם אַנְשֵׁ֖י מַצֻּתֶ֑ךָ יִהְי֥וּ כְאַ֛יִן וּכְאֶ֖פֶס אַנְשֵׁ֥י מִלְחַמְתֶּֽךָ׃
Thou shalt seek them, and shalt not find them, Even them that contended with thee; They that warred against thee Shall be as nothing, and as a thing of nought.
Read halakhic rulings (Jewish law) on Isaiah 41:12: and classical halakhic sources.