Brook of Egypt

The Brook of Egypt is the name used in some English translations of the Bible for the Hebrew Nachal Mitzrayim ("River of Egypt") used for the river defining the westernmost border of the Land of Israel. Popular Bible commentaries identify it with Wadi El-Arish although the identification is problematic. Early Aramaic translations and Jewish commentaries identify it with the Nile or more precisely the Pelusian arm of the Nile — a no longer extant branch of the Nile lying on the border of Ancient Egypt. Modern archaeological surveys have shown that the course of the Nile changed over time and that the Nachal Mitzrayim was an ancient easternmost branch of the Nile whose course differed from that of the later Pelusian branch. The related phrase is Nahar Mitzrayim, used in Genesis 15:18. This also means "river of Egypt", and is generally recognized as referring to the Nile, or its eastern branch (2 Chr. 9:26).

The traditional Jewish understanding of the term Nachal Mitzrayim is that it refers to the Nile. This view is made explicit in the Jerusalem Targum, the Targum Jonathan, the Targum Neofiti and the Fragment Targums (where in all cases the term is translated Nilus) as well as in the commentaries of Rashi and Rabbi Yehuda Halevi. Rashi explicitly states in his commentary on Joshua 13:3

"From the Shihor: that is the Nile the same as Nachal Mizraim."

Nevertheless, the term Nachal Mitzrayim is only used when discussing the border of the Land of Israel whereas Ye'or is typically used for the main body of the Nile. This suggests that there is indeed some difference in meaning. Since the Land of Israel did not extend into the Nile Delta the most probable interpretation of the term is that it refers specifically to the Delta or the Pelusian arm of the Nile. Rabbi Yehuda Halevi explicitly identified it with the Pelusian arm.

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