Rashi says that Yehuda was very tough with Yosef, and he threatened to kill him and Paroh together. Chazal say that Yehuda was ready to destroy the entire Mitzrayim and he started issuing orders to his super strong brothers. Yet, in the Pesukim we see tremendous Eidelkeit. He keeps calling Yosef: אֲדֹנִי my master, and himself and his brothers and his father: עַבְדְךָ your slave. He speaks with warmth and caring, soft as butter. The true Anav who is capable to be tough, but he isn’t. (Sifrei Mussar).
Why doesn’t Yehuda just finish him off? He and his brothers had destroyed many Canaani cities; they were all highly successful: מְלֻמְדֵי מִלְחָמָה seasoned fighters. Why do they hesitate? Why should they even be: גוֹרֵס (notice) such an evil royal tyrant, whom they thought Yosef was? The answer is that in last week’s Parsha they said: הָאֱלֹקִים מָצָא אֶת עֲוֹן עֲבָדֶיךָ Hashem has found the place to collect payment for our sin, and: מַה זֹּאת עָשָׂה אֱלֹקִים לָנוּ Why is Hashem doing this to us? All they talked about was their: חַשַּׁשׁ fear that Hashem was punishing them for the only sin they ever did, i.e.: מְכִירַת יוֹסֵף selling their brother Yosef for a slave. (Chazal).
