Numbers 34:12
And the border shall go down to Jordan, and the goings out of it shall be at the salt sea: this shall be your land with the coasts thereof round about. And the border shall go down to Jordan, and the goings out of it shall be at the salt sea: this shall be your land with the coasts thereof round about.
The eastern line was fixed in advance as part of the limits of Canaan as the territory to be divided among the tribes upon their coming into possession of it. On that side the border was to run down to the Jordan and terminate at the Salt Sea, thus marking out the land with its surrounding coasts. The apportionment was to embrace the entire country so defined, including both the districts already conquered and those still unsubdued.
The work of distribution was entrusted to Joshua, Eleazar the high priest, and the heads of the tribes, with the place of each tribe to be settled by lot and a prince from each tribe designated to oversee the allotment. Each tribe was then charged with the responsibility of fully subduing its own inheritance, under the assurance that faithfulness to God would bring the expulsion of its enemies from before it and even larger possessions for continued loyalty to His covenant. Levi was excluded from this territorial division on account of its consecration to sanctuary service, receiving instead forty-eight cities scattered in different parts of the land as its inheritance.