Genèse 20:1

And Abraham went on from thence to the land of the south, and dwelt between Rekam and Chagra, and had his habitation in Gerar.

וישב בין קדש ובי שור, between 2 large cities, in order to have an opportunity to proclaim the holy name of G’d in both these cities, as he did later, the objective being to improve G’d’s image among mankind.

ויסע משם, from Eloney Mamre, the place where he resided most of the time. The Torah fails to mention what prompted Avraham to leave his home in this fashion. It could not have been due to the famine, seeing that at that time no famine is reported as having existed in that region, as opposed to when Yitzchok left his home and went to the land of the Philistines as reported in 26,1. Seeing that in that connection the Torah referred to this famine as being additional to the one in the days of Avraham, and we know that at that time Avraham went to Egypt and did not settle in the region between Kadesh and Shur, we cannot attribute his move to a famine. Perhaps what motivated Avraham was the need to fulfill the commandment by G’d to dwell in all parts of the land of Canaan. The Torah would indicate, obliquely, that the land of the Philistines was included in what G’d had described as “the land of Canaan,” even though the Philistines were distant descendants of Mitzrayim, a grandson of Cham but not directly descended from Canaan. Eventually, the coastal plain inhabited by the Philistines became part of the tribal territory of Yehudah. This may be why the Torah refers to this as ארצה הנגב, the southern region, seeing that Yehudah’s territory is described as the southern part of the country in Joshua chapter15.

וישב בין קדש ובין שור, the Torah did not bother to tell us precisely where Avraham settled. Later on, we are told that he settled in Gerar, the capital of the land of the Philistines. The part of the verse mentioning this fact is not related to the earlier part of the verse. Besides, the terms וישב and ויגר are totally different from one another, the former speaking of someone settling down with a view to remaining there for a long period, whereas the term ויגר always reflects the intention of the person described to remain there only for a relatively brief period of time, as for instance in Genesis 37,1 where when Yaakov settled down, the Torah contrasts this with the fact that his father and grandfather could not settle down there permanently but had only sojourned there,מגורי אביו. It is customary for Scripture to employ different words when repeating basically the same message. Perhaps, initially, Avraham had settled in one of the locations in the regions such as באר לחי רואי, subsequently moving to Gerar, seeing that באר לחי רואי was situated between Kadesh and Shur, as we know from Genesis 16,4.