Powtórzonego Prawa 17:16 Halacha: Mishneh Torah, Kings and Wars, Mishneh Torah, Negative Mitzvot & Sefer HaChinukh

Israel was enjoined with three Commandments upon entering the Land: to appoint a king, as it says, “you shall set a king over yourselves” (Deut. 17:15); to destroy the descendents of Amalek, as it says “erase the memory of Amalek” (Deut. 25:19); and build the Temple, as it says, “you shall seek His habitation, and there you will come” (Deut. 12:5).

"He must not accumulate many horses" (Deut. 17:16), but only as many as he needs for his chariots²³For war.. He may not even have one spare horse to trot before him, as is done before other kings. If he adds, he is given stripes.

It is permissible to live anywhere in the world, except for Egypt, defined as the area extending west of the Mediterranean Sea, 400 Parsangs by 400 Parsangs, in the direction of Ethiopia and in the direction of the desert. The Torah warned us in three places not to return to Egypt, “and do not return in this way again” (Deut. 17:16), and “and you shall no longer see it” (Deut. 28:68), and “And you shall not ever again see it” (Exodus 14:13). Alexandria is included in this prohibition.