The lion has roared, who will not fear?!
By analogy: Who would not be afraid of such a thing?! Everyone was afraid upon hearing his voice.
("The lion has roared, who will not fear? The Lord GOD has spoken, who can but prophesy?" – Amos 3:8)
Translation
Expression (Hebrew)
אַרְיֵה שָׁאָג מִי לֹא יִירָא?!
Definition (Hebrew)
בְּהַשְׁאָלָה: מִי לֹא יְפַחֵד מִדָּבָר כָּזֶה ?! כֻּלָּם פָּחֲדוּ לְשֵׁמַע קוֹלוֹ.
("אַרְיֵה שָׁאָג מִי לֹא יִירָא, אֲדֹנָי ה' דִּבֶּר מִי לֹא יִנָּבֵא"- עָמוֹס ג ח)