Why did he assume that the name “Yoktan” was of any significance? Rashi perhaps sought to explain why Yoktan – a man otherwise shrouded in obscurity – was deserving of so many children, and for this reason he interpreted the name “Yoktan” as an allusion to the man’s exceptional virtue of modesty.
In the latter section of Parashat Noach (chapters 10-11) the Torah presents a genealogical record of the descendants of Noach’s three sons. We read that Eiver, a great-grandson of Noach’s son Shem, begot two sons named Peleg and Yoktan (10:25). Peleg, we are told, was so named because “the land was dispersed” during his lifetime, presumably referring to the incident of Migdal Bavel (the Tower of Babel), of which we read in the next section. (We should note, however, that Rashi, in Divrei Hayamim I 1:20, explains this phrase differently.) As Rashi cites from the Midrash, Eiver prophetically foresaw this cataclysmic event at the time of Peleg’s birth, and named him accordingly.
Commenting on the following verse, which begins to list the names of Yoktan’s children, Rashi tells us that his name, too, has etymological significance, and originates from the word katan – small. Citing from the Midrash, Rashi writes that Yoktan conducted himself very humbly, and was rewarded for his unassuming character with thirteen sons.
The Targum Rav Yosef (the Aramaic translation of Divrei Hayamim) in Divrei Hayamim I (1:20) gives a different explanation of the word “Yoktan,” namely, that life expectancy began to sharply decline during his time. Indeed, a review of the final section of Parashat Noach (11:10-32) reveals that people began to live considerably shorter lives after Eiver’s death. Eiver lived 464 years (11:16-17), whereas his son, Peleg, lived just 239 years, as did his grandson, Re’u. This progression continued steadily in the next generations (with the exception of Nachor’s relatively short lifespan): Serug – 230; Nachor – 148; Terach – 205; Avraham – 175.
Rav Eliyahu Mizrachi, in his work on Rashi’s commentary, addresses the question of why Rashi felt compelled to suggest an interpretation for Yoktan’s name. Why did he assume that the name “Yoktan” was of any significance? Rav Eliyahu Mizrachi suggests that the connection between the name “Yoktan” and the word katan is clear and evident, and we should therefore assume that Eiver (and perhaps his wife) had this in mind when choosing this name. Indeed, Rav Eliyahu Mizrachi notes, one of Yoktan’s sons was named Chatzarmavet, and the Midrash (briefly paraphrased by Rashi on this verse; see notes in the Torat Chayim Chumash), finds significance in the connection between this name and the word mavet (death). Rav Eliyahu Mizrachi further suggests that Eiver’s having named Peleg for a specific event might have led one to believe that Yoktan was likewise named for a particular event that occurred during his lifetime. Rashi therefore sought to clarify that Yoktan was so named because of his remarkable humility, rather than for some historical event. Rav Eliyahu Mizrachi expresses his strong preference for the first explanation he proposed.
Rav Shlomo Ha-kohen of Vilna, in his work Binyan Shelomo (cited in the compendium Ke-motzei Shalal Rav), claims that Rav Eliyahu Mizrachi’s entire discussion overlooks Rashi’s explicit remarks in his commentary to Sefer Divrei Hayamim I (1:20). Rashi there comments that the names of other people of this time are not subject to etymological analysis because they were not assigned prophetically. Eiver, as the Midrash tells, was a prominent prophet, and his sons’ names thus have deep significance; the same cannot be said of the other people mentioned in this list. For this reason, the Binyan Shelomo contends, Rashi found it necessary to analyze Yoktan’s name because it was given to him by his father, a distinguished prophet.
It should be noted that in Divrei Hayamim Rashi does not actually say that Eiver’s prophetic powers compel us to interpret the name his gave Yoktan; Rashi merely writes that other names do not lend themselves to interpretation because they were not prophetically assigned.
We might suggest a simpler reason why Rashi found it necessary to comment on Yoktan’s name. It is perhaps revealing that Rashi does not comment on the Torah’s initial mention of Yoktan (“and his [Peleg’s] brother’s name was Yoktan” – 10:25); he makes his remarks only on the next verse – “And Yoktan begot Almodad, Shalef, Chatzarmavet…” This might indicate that what motivated Rashi’s analysis of Yoktan’s name was not the name itself, but rather the Torah’s list of his children’s names. As mentioned earlier, Yoktan begot thirteen sons – a much higher number of children than we find among other people mentioned in these genealogical records. Rashi perhaps sought to explain why Yoktan – a man otherwise shrouded in obscurity – was deserving of so many children, and for this reason he interpreted the name “Yoktan” as an allusion to the man’s exceptional virtue of modesty. This also explains why Rashi felt it necessary to conclude his remarks by commenting, “He therefore earned the merit of establishing all these families.” This clearly suggests that Rashi here seeks to explain not the name Yoktan, but rather why he – more than the other personalities listed in this chapter – was blessed with so many children who themselves founded large families.