Ophir, Havilah, and Jobab; all these were the sons of Joktan.
Two things especially are observable in this account of the posterity of Shem: - I. The description of Shem, Gen 10:21. We have not only his name, Shem, which signifies a name, but two titles to distinguish him by: - 1. He was the father of all the children of Eber.
Commenting on Genesis 10:21-32
And Ophir, and Havilah, and Jobab,.... If several of the sons of Joktan went into India, as the Arabs say, one would be tempted to think that Ophir in India, whither Solomon sent his ships once in three years, had its name from the first of these; See Gill on Gen 10:26 but as this would be carrying him too far from the rest of...
Gen 10:25-29 Among the descendants of Arphaxad, Eber’s eldest son received the name of Peleg, because in his days the earth, i.e., the population of the earth, was divided, in consequence of the building of the tower of Babel (Gen 11:8). His brother Joktan is called Kachtan by the Arabians, and is regarded as the father of all the primitive tribes of Arabia.
Commenting on Genesis 10:25-29