וְלֹא־הָ֥יָה מַ֖יִם לָעֵדָ֑ה וַיִּקָּ֣הֲל֔וּ עַל־מֹשֶׁ֖ה וְעַֽל־אַהֲרֹֽן׃
And there was no water for the congregation; and they assembled themselves together against Moses and against Aaron.
Read kabbalistic (mystical) interpretation of Numbers 20:2: and classical mystical sources.