Jeremiah 13:2 Kabbalah

וָאֶקְנֶ֥ה אֶת־הָאֵז֖וֹר כִּדְבַ֣ר יְהוָ֑ה וָאָשִׂ֖ם עַל־מָתְנָֽי׃ (ס)

So I got a girdle according to the word of the LORD, and put it upon my loins.

Read kabbalistic (mystical) interpretation of Jeremiah 13:2: and classical mystical sources.