All Descendants of Yaakov - Jews
Are Called Yehudim
Yehudah was honored more than all his brothers in that all descendants of Yaakov are called Yehudim ("Jews," lit. "Judah-ites" Bereishit Rabbah 98:6).
His superiority was recognized by his brothers who appointed him their king (Bereishit Rabbah 84:17).
Yehudah earned these distinctions for saving Yosef's life, for his candor in confessing his relationship with Tamar (Bereishit 38:1–27), and for his admirable traits of character. Although it was at his suggestion that Yosef was sold rather than put to death, Yehudah should nevertheless have returned him to their father (Bereishit Rabbah 85:3).