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.
Read kabbalistic (mystical) interpretation of Genesis 45:3: and classical mystical sources.