قُلْ كَفَىٰ بِٱللَّهِ بَيْنِى وَبَيْنَكُمْ شَهِيدًا ۖ يَعْلَمُ مَا فِى ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضِ ۗ وَٱلَّذِينَ ءَامَنُوا۟ بِٱلْبَـٰطِلِ وَكَفَرُوا۟ بِٱللَّهِ أُو۟لَـٰٓئِكَ هُمُ ٱلْخَـٰسِرُونَ
Qul kafaa billaahi bainee wa bainakum shaheedaa; ya'lamu maa fis samaawaati wal ard; wallazeena aamanoo bil baatili wa kafaroo billaahi ulaaa'ika humul khaasiroon
Say: God is sufficient as witness between me and you. He knows what is in the heavens and the earth. Those who believe in falsehood and deny God — it is they who are the losers.
Both ordinary religious verbs turn up in the final clause with their objects exchanged: belief given to what is empty, rejection aimed at God. Calling that loss locates the failure in the direction of a conviction held firmly, since these are people with a settled position. The opening moves the dispute onto legal ground, where a claim two parties cannot settle between them is referred to a witness.