Why Leah Praised Only at Judah's Birth and Jacob Blessed Him

(Gen. 49:6) "FOR IN THEIR ANGER THEY KILLED A MAN." When they killed Shechem ben Hamor, he [Jacob] said to them: "You have brought trouble upon me." Immediately (Gen. 49:7): "CURSED BE THEIR ANGER, FOR IT WAS FIERCE." These tribes are not able to dwell as one; rather, "I WILL DIVIDE THEM IN JACOB AND SCATTER THEM IN ISRAEL." Judah entered, and he [Jacob] praised him: (Gen. 49:8) "JUDAH, YOU — YOUR BROTHERS SHALL PRAISE YOU." Through your name your mother gave praise when your mother bore you: (Gen. 29:35) "THIS TIME I WILL PRAISE THE LORD." And what did she see, to give praise to the LORD? Rather: she bore Reuben, and she foresaw Dathan and Abiram, and she did not give praise over him. She bore Simeon and foresaw Zimri, and she did not give praise over him. She bore Levi and foresaw Korah, and she did not give praise over him. When she bore Judah, immediately she gave praise over him, for he confessed in the matter of Tamar, as it is said (Gen. 38:26): "AND JUDAH RECOGNIZED, AND HE SAID: SHE IS MORE RIGHTEOUS THAN I." His father said to him: Your mother gave praise over you, and you confessed; therefore "your brothers shall praise you." When Isaac blessed Jacob, he said to him (Gen. 27:29): "AND MAY YOUR MOTHER'S SONS BOW DOWN TO YOU," for he [Isaac] had but one wife. But Jacob, who had four wives, said: "your father's sons." Why "your brothers shall praise you"? For all Israel shall be called by your name, "Yehudim" [Jews]. And not only that, but the Messiah comes forth from you, who saves Israel, as it is said (Isa. 11:1): "AND A SHOOT SHALL COME FORTH FROM THE STEM OF JESSE."