Quran 2:76 Al-Baqarah, ayah 76 of 286

وَإِذَا لَقُوا۟ ٱلَّذِينَ ءَامَنُوا۟ قَالُوٓا۟ ءَامَنَّا وَإِذَا خَلَا بَعْضُهُمْ إِلَىٰ بَعْضٍ قَالُوٓا۟ أَتُحَدِّثُونَهُم بِمَا فَتَحَ ٱللَّهُ عَلَيْكُمْ لِيُحَآجُّوكُم بِهِۦ عِندَ رَبِّكُمْ ۚ أَفَلَا تَعْقِلُونَ ۝٧٦

2:76 And when they fall in with those who believe, they say: We believe. But when they go apart one with another they say: Prate ye to them of that which Allah hath disclosed to you that they may contend with you before your Lord concerning it? Have ye then no sense?