PERMISSION TO SIT H 839 "No one should sit between two persons without their permission." R 839 Abu Daud related that the Prophet, praise and peace be upon him, said this.
828- وفي رواية لأبي داود : "لاَ يُجْلسُ بَيْنَ رَجُلَيْنِ إِلاَّ بِإذْنِهِمَا" .