El Topo (1970)
La mujer: [after taking a drink from a river] It's bitter.
El Topo: [while stirring the river water with a tree branch] Moses found water in the desert. The people tried to drink it, but were unable to because it was bitter. They named the water Marah.
La mujer: [after taking another drink from the river] It has turned sweet!
El Topo: I shall call you Marah, because you are bitter like water.