وَعَنْهُ أَيْضًا عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قَالَ إِذَا كُنْتُمْ ثَلَاثَةً فَلَا يَتَنَاجَى اثْنَانِ دُونَ صَاحِبِهِمَا قَالَ قُلْنَا فَإِنْ كَانُوا أَرْبَعًا قَالَ فَلَا يَضُرُّ
It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: When you are three people, then two of you should not whisper to each other leaving the third one out. Abu Salih, the narrator, said: What if there are four people? He (Ibn Umar) said: Then this does not cause any harm (i.e., then there is no problem).