פירוש על מלכים א 2:34

In his own house in the wilderness. For his home was unrestricted as a wilderness, to [help] the needy.²³See Rashi in Maseches Sanhedrin 49a. Alternatively, Yoav had a house in the wilderness where his shepherds stayed when they were out with the sheep, or Yoav house was free of stolen property just like the wilderness.—Radak.