בראשית, פרק ל״ו, פסוק ל״ז

The succession of leadership in the kingdom of Edom continues with the rise of a new king named Shaul, who originates from a city known as Rechovot, situated along the banks of a prominent waterway. A well-established rule in biblical geography dictates that whenever a river is mentioned without a specific name, it refers directly to the Euphrates. This is the same major river introduced as the fourth river at the very beginning of the Torah. Because Rechovot is located along the Euphrates, it is geographically identified as the ancient city of Pethor [ביאור יש״ר].