Land Promised & Given to him by the Holy Prophet (sa)
The Holy Prophet (sa) gave accommodation in Medina to a number of tribes and companions. He provided the tribe of Hazrat Abdur Rahman (ra) bin Auf a place to dwell in a land beside the Mosque of the Prophet, which was clustered with date trees. Furthermore, he granted Hazrat Abdur Rahman (ra) bin Auf and Hazrat Umar (ra) some land. Later, Hazrat Zubair (ra) then purchased this land from the family of Hazrat Umar (ra), namely from his children. The Holy Prophet (sa) even vouchsafed to Hazrat Abdur Rahman (ra) bin Auf that when the Muslims conquer Syria, he would have such and such portion of land. Thus, when the Muslims were victorious in Syria during the Khilafat of Hazrat Umar (ra), Hazrat Abdur Rahman (ra) bin Auf was given those lands promised to him and that area which was promised to him was known as Salil.
(Roshan Sitarey az Ghulam Bari Saif Sahib, Vol. 2, pp. 105-106)