Al-Baqarah 2:76
وَإِذَا لَقُوا الَّذِينَ آمَنُوا قَالُوا آمَنَّا وَإِذَا خَلَا بَعْضُهُمْ إِلَىٰ بَعْضٍ قَالُوا أَتُحَدِّثُونَهُم بِمَا فَتَحَ اللَّهُ عَلَيْكُمْ لِيُحَاجُّوكُم بِهِ عِندَ رَبِّكُمْ ۚ أَفَلَا تَعْقِلُونَ ٧٦
Waitha laqoo allatheena amanoo qaloo amanna waitha khala baAAduhum ila baAAdin qaloo atuhaddithoonahum bima fataha Allahu AAalaykum liyuhajjookum bihi AAinda rabbikum afala taAAqiloona
And (they have reached such a state that) when they meet the believers, they say: ‘We (too) have believed (in Muhammad [blessings and peace be upon him], like you),’ and when they are together in isolation, they say: ‘Do you tell them (the Muslims) that which Allah has unfolded to you (through the Torah in connection with the Prophethood and glory of the last of the Prophets, Muhammad, [blessings and peace be upon him]) so that they may use it in argument against you in the holy presence of your Lord? Do you not have (even this much) sense?’ (2:76)