וַיִּקְרַ֤ע יַעֲקֹב֙ שִׂמְלֹתָ֔יו וַיָּ֥שֶׂם שַׂ֖ק בְּמָתְנָ֑יו וַיִּתְאַבֵּ֥ל עַל־בְּנ֖וֹ יָמִ֥ים רַבִּֽים׃
And Jacob rent his garments, and put sackcloth upon his loins, and mourned for his son many days.
Read kabbalistic (mystical) interpretation of Genesis 37:34: and classical mystical sources.