בָּעֵ֣ת הַהִ֗יא דִּבֶּ֣ר יְהוָה֮ בְּיַ֣ד יְשַׁעְיָ֣הוּ בֶן־אָמוֹץ֮ לֵאמֹר֒ לֵ֗ךְ וּפִתַּחְתָּ֤ הַשַּׂק֙ מֵעַ֣ל מָתְנֶ֔יךָ וְנַעַלְךָ֥ תַחֲלֹ֖ץ מֵעַ֣ל רַגְלֶ֑יךָ וַיַּ֣עַשׂ כֵּ֔ן הָלֹ֖ךְ עָר֥וֹם וְיָחֵֽף׃ (ס)
at that time the LORD spoke by Isaiah the son of Amoz, saying: ‘Go, and loose the sackcloth from off thy loins, and put thy shoe from off thy foot.’ And he did so, walking naked and barefoot.
Read halakhic rulings (Jewish law) on Isaiah 20:2: and classical halakhic sources.