וַיַּסַּ֨ע מֹשֶׁ֤ה אֶת־יִשְׂרָאֵל֙ מִיַּם־ס֔וּף וַיֵּצְא֖וּ אֶל־מִדְבַּר־שׁ֑וּר וַיֵּלְכ֧וּ שְׁלֹֽשֶׁת־יָמִ֛ים בַּמִּדְבָּ֖ר וְלֹא־מָ֥צְאוּ מָֽיִם׃
And Moses led Israel onward from the Red Sea, and they went out into the wilderness of Shur; and they went three days in the wilderness, and found no water.
Read kabbalistic (mystical) interpretation of Exodus 15:22: and classical mystical sources.