All Dungeons and Dragons edition I'm familiar with have its Cleric character class. Apparently, D&D Cleric is a trope of its own.
Many D&D "clerical" spells were still inspired by popular fantasy tropes, like priests' blessings and healing hands. However, the Create Water spell seems to stand out, in that it seems less archetypal associated with its class (clerics/priests) than the others.
It is neither a rainmaking ritual, nor a divination ability that helps to find water. It is an ability to make water appear out of nothing, and it's clerical for some reason. I can't remember any older fantasy book or movie where clerics actually do that.
Does the idea of priests/clerics having a water-creation ability exist in any earlier source (including mythology and religious texts), or is it an original D&D invention, like the Cleric class itself?