Keilim 1:6-7

Keilim 1:6

There are also ten levels of sanctity. Israel is holier than other lands. Its sanctity is that we can bring the omer (a measure of barley), first fruits and the two loaves (on Shavuos) from the produce of Israel but not from those of any other land.

Keilim 1:7

Walled cities (from the time of Joshua) are holier than elsewhere in Israel because we send those with tzaraas (“leprosy,” but not really) out from them, and a corpse may be carried around within a walled city until they decide to remove it for burial. Once it has been brought out, it may not be brought back in.