וַיֹּ֨אמֶר יוֹסֵ֤ף אֶל־אֶחָיו֙ אֲנִ֣י יוֹסֵ֔ף הַע֥וֹד אָבִ֖י חָ֑י וְלֹֽא־יָכְל֤וּ אֶחָיו֙ לַעֲנ֣וֹת אֹת֔וֹ כִּ֥י נִבְהֲל֖וּ מִפָּנָֽיו׃
And Joseph said unto his brethren: ‘I am Joseph; doth my father yet live?’ And his brethren could not answer him; for they were affrighted at his presence.
Rashi on Genesis
נבהלו מפניו [FOR] THEY WERE AMAZED AT HIS PRESENCE — out of shame.
Sforno on Genesis
העוד אבי חי?, “how could he have survived so many years of worry over my fate?”
Radak on Genesis
ויאמר, After Joseph had finished weeping he told his brothers אני יוסף.