Commentaire sur Les Nombres 21:15

ואשר הנחלים THE DISCHARGE IN THE VALLEYS — The Targum translation of ,שפך “pouring forth”, is אשר. Consequently these words signify “the pouring forth in the valleys”, for at that place there was poured forth the blood of the Amorites who had concealed themselves there. As the mountains were high and the valley deep and narrow, and the mountains were so close to one another, that a man could stand upon the mountain on one side and speak to his fellow on the other mountain, and the road passed through the valley, the Amorites said: When the Israelites are about to enter the land by passing through the valley we will come out of the mountain caves above them and will kill them by arrows and stone missiles. Now those caves were in the mountains on the Moabite side, and on the mountain that was on the Amorite side there were, opposite those caves, projections like horns and breasts jutting out. When Israel were on the point of passing, the mountain that was located in the land of Israel (that on the Amorite side which afterwards came into the possession of the Israelites) was set in tremor as a handmaid that goes forth to receive her mistress, and moved nearer to the mountain of Moab, and these breast-like projections penetrated into the caves and killed them (the Amorites who were hidden in them). And this is the meaning of אשר נטה לשבת ער which inclineth towards the dwelling (location) of Ar (the capital Moab) — which means that the mountain inclined from its place and approached close to the mountain on the Moabite side and affixed itself to it: and this, too, is the meaning of ונשען לגבול מואב, and leaneth towards the boundary of Moab (Midrash Tanchuma, Chukat 20; cf. Berakhot 54b).

When the Israelites came to pass through, the Eretz Yisroel mountain was set in tremor. (Gur Aryeh) You might ask: The mountain should have returned to its place immediately, such that the Israelites would have seen the dead in the valley. Why then did the mountain only return to its place after they had passed through? The answer is that it is not proper for one who receives his master to return to his place until his master passes, therefore [the mountain] did not return to its place until the Israelites had passed. Kitzur Mizrochi raises a difficulty: We need not ask that surely the cloud went before them, flattening any heights and raising any low places, and as a result the mountain should have returned immediately. Here we cannot answer that the cloud had already departed at Aharon’s death, for the Gemara in Maseches Taanis (9a) states that it returned in the merit of Moshe. Nonetheless, this is not a difficulty because the cloud traveled three days journey ahead of them, thus it is possible that at the time of passing through, the mountain had not yet accomplished its task of killing those who gathered there. Consequently the cloud did not level out the mountain.

ואשד הנחלים, “as well as its tributary wadis.” We find the word אשד also in Deuteronomy 3,17, i.e. אשדות (in the plural mode)

ואשד הנחלים, this was another location that the Israelites were not allowed to invade as part of it was overhanging airspace belonging to the Moabite Kingdom.

אשר נטה לשבת ער, “stretched along settled country.” Seeing that these valleys seemed to overhang territory belonging to Moav, that latter began to settle in it. At any rate, at the time of writing these lines both banks of the river Arnon were populated. [The reason why this is all spelled out become clear when we read about how the Jewish people had been saved by an earthquake turning fatal for the Emorites who had planned an ambush in the clefts of the protruding rocks. [Compare the Midrashim on verses 17-19 of this chapter. Ed]