Komentarz do Diwrej ha-jamim I 7:1

And of the sons of Issachar: Tola, and Puah, and Jashub, and Shimron In the Pentateuch (Gen. 46:13) it is written: “and Job.” Job was his name [originally], but since they settled themselves (נִתְיַשְּׁבוּ) to learn Torah, as it is written (below 12:33): “And of the sons of Issachar, who possessed understanding of the times,” he merited and was called Jashub (יָשוּב).