وَقَالَ مُوسَىٰ رَبِّىٓ أَعْلَمُ بِمَن جَآءَ بِٱلْهُدَىٰ مِنْ عِندِهِۦ وَمَن تَكُونُ لَهُۥ عَـٰقِبَةُ ٱلدَّارِ ۖ إِنَّهُۥ لَا يُفْلِحُ ٱلظَّـٰلِمُونَ Qur’an Al-Qasas (28:37)Waq a la moos a rabbee aAAlamu biman j a a bi a lhud a min AAindihi waman takoonu lahu AA a qibatu a l dd a ri innahu l a yufli h u a l thth a limoon a
For an explanation of the above phrase, see surah {6}, note [118].
Cf. vi. 135. The only argument in such a case is an appeal to Allah, and to the ultimate Future. Both of these appeals require Faith. But even if you do not rely on anything so high, you can see that Falsehood or evils crystallised in ancestral customs are not going to do any one any good.