כֹּֽה־אָמַ֨ר יְהוָ֜ה אֵלַ֗י הָל֞וֹךְ וְקָנִ֤יתָ לְּךָ֙ אֵז֣וֹר פִּשְׁתִּ֔ים וְשַׂמְתּ֖וֹ עַל־מָתְנֶ֑יךָ וּבַמַּ֖יִם לֹ֥א תְבִאֵֽהוּ׃
Thus said the LORD unto me: ‘Go, and get thee a linen girdle, and put it upon thy loins, and put it not in water.’
Read kabbalistic (mystical) interpretation of Jeremiah 13:1: and classical mystical sources.