847. Willows of the Brook
“Willows of the brook that grow by the stream, etc., Rabbi Zira said, ‘Why is it called ‘It is rooted by abundant water’; its name is a willow’?” (Sukkah 34, Ezekiel 17). This means that although they have neither taste nor smell, it is still as though there is abundant water here.
Water means “upper abundance.” It is as though one feels in it a good taste and pleasantness, and derives from this joy, gladness, and merriment, from belonging to a people that is filled with delight, meaning that with their actions, they serve the King.