3,220. The Three Categories of Land

Terumos 1:6

We have seen that the whole world is divided into three groups vis-a-vis the mitzvos of the land: Israel, Syria and outside of Israel. Israel is subdivided into areas that were settled by the Jews who returned from Babylonia and areas that were only settled by the Jews who came from Egypt. Outside of Israel is divided into Egypt, Babylonia, Ammon and Moab – i.e., lands in which the mitzvos of the land are observed by rabbinic enactment, and all other lands where terumah and tithes are not observed.

Terumos 1:7

The land settled by the Jews who came from Egypt is from Rekem in the east until the Mediterranean Sea and from Ashkelon in the south until Acco in the north. Traveling from Acco to K’ziv, the land to the right, i.e., the east, can be assumed to be outside of Israel – ritually unclean like the lands of other nations and exempt from tithes and shemittah. This is the case unless some area is known to be part of Israel. The land to the left, i.e., the west, can be assumed to be part of Israel – ritually clean and obligated in tithes and shemittah, unless it is known to be outside of Israel. Regarding the area that slopes down from the Samnum mountains (near Ashkelon, in the south), the inner part is Israel and the part outside the mountains is outside of Israel. When it comes to the islands of the sea, we extend a mental line from the Samnum mountains until the Nile River* in Egypt. Those islands that fall within the line are part of Israel, while those outside the line are outside of Israel. 

*Probably.