Nothing said in private is actually private

أَلَمْ تَرَ أَنَّ ٱللَّهَ يَعْلَمُ مَا فِى ٱلسَّمَـٰوَٰتِ وَمَا فِى ٱلْأَرْضِ ۖ مَا يَكُونُ مِن نَّجْوَىٰ ثَلَـٰثَةٍ إِلَّا هُوَ رَابِعُهُمْ وَلَا خَمْسَةٍ إِلَّا هُوَ سَادِسُهُمْ وَلَآ أَدْنَىٰ مِن ذَٰلِكَ وَلَآ أَكْثَرَ إِلَّا هُوَ مَعَهُمْ أَيْنَ مَا كَانُوا۟ ۖ ثُمَّ يُنَبِّئُهُم بِمَا عَمِلُوا۟ يَوْمَ ٱلْقِيَـٰمَةِ ۚ إِنَّ ٱللَّهَ بِكُلِّ شَىْءٍ عَلِيمٌ

“Have you not considered that Allāh knows what is in the heavens and what is on the earth? There are not three in a private conversation but that He is the fourth of them,1 nor are there five but that He is the sixth of them - and no less than that and no more except that He is with them [in knowledge] wherever they are. Then He will inform them of what they did, on the Day of Resurrection. Indeed Allāh is, of all things, Knowing.”