6-Surah Al-An’am ( The Cattle ) 150
Say, [O Muhammad], ‘ Bring forward your witnesses who will testify that Allah has prohibited this.’ And if they testify, do not testify with them. And do not follow the desires of those who deny Our verses and those who do not believe in the Hereafter, while they equate [others] with their Lord.
قُلْ هَلُمَّ شُهَدَاءَكُمُ الَّذِينَ يَشْهَدُونَ أَنَّ اللَّهَ حَرَّمَ هَٰذَا ۖ فَإِن شَهِدُوا فَلَا تَشْهَدْ مَعَهُمْ ۚ وَلَا تَتَّبِعْ أَهْوَاءَ الَّذِينَ كَذَّبُوا بِآيَاتِنَا وَالَّذِينَ لَا يُؤْمِنُونَ بِالْآخِرَةِ وَهُم بِرَبِّهِمْ يَعْدِلُونَ
Quran's Tafhim ( explanation)
*126). A person who is conscious that he should testify only to that which he knows, can never testify that the taboos regarding food and other customs prevalent in their society had been enjoined by God. But if some people are brazen enough to feel no compunction in bearing false witness, then at least the believers should not become their partners in lying. The real purpose in asking them to testify honestly whether their customs and practices had in fact been sanctioned by God, is to stimulate those with some sense of honesty to reflect on the character of their customs and practices. Perhaps when they realize that there is no evidence of those prohibitions having been prescribed by God, some of them may decide to get rid of them.