Why Judah Went Down and His Brothers Deposed Their King

Midrash Tanchuma Buber, Vayeshev 12:1

(Gen. 38:1:) "And Judah went down." What is the meaning of "went down"? That they brought him down from his greatness. Why? Because they had appointed him king over them. When they sold Joseph, they came to their father to comfort him, but he refused to be comforted. They said: Now the old man holds a grievance against us. What did they do? They arose and banished him (Judah), as it is said, "And Judah went down."

Themes

Biblical References