Halakhah do Rodzaju 15:18

Insofar as the Negev and the southern territories are concerned, the Mishnah, Gittin 2a, indicates that Ashkelon was the southern boundary of Erez Yisra'el. Rambam maintains that those who ascended from Egypt conquered no territory south of Ashkelon and that Ashkelon was always the southern boundary. However, most other authorities maintain that in the time of Joshua territories south of Ashkelon were also captured and that the Mishnah, in speaking of Ashkelon as the southern border, refers only to areas regained in the time of Ezra and gives the boundary which existed in the time of the Second Commonwealth. According to these authorities, at least some of the areas south of Ashkelon fall into the category of territory captured by those who ascended from Egypt but not retaken by the returnees from Babylonia. There is considerable evidence in support of this view. I Kings 8:65 speaks of the south of Israel as being populated by Jews "until the river of Egypt." Targum Yonatan (Genesis 15:18) translates the words "nahar mizrayim" as the "Nile of Egypt." Radbaz, Hilkhot Terumot 1:7, dismisses this view and declares the river to be Wa'ad al Arish. This is also the opinion of Sa'adia Ga'on.¹⁴See Tevu’ot ha-Areẓ, chap. 1, p. 27. Sa'adia Ga'on states that Ma'aleh Akrabim of Numbers 34:4 is identical with the area known as Aqaba. I Kings 9:26 speaks of Solomon's dominion as extending to Eilat; II Kings 14:22 and II Chronicles 26:2 speak of the rebuilding of Eilat by Uzziah. It is, however, generally assumed that these territories were not resettled by those who returned with Ezra.