The Aravah and the Simple Jew

On Hoshana Rabbah, the main mitzvah is only with the aravah. All the “Four Kinds” reflect the concept of unity; only the willow branch is united not only in and of itself, but also with other willows, growing as it does in clusters, since it is permeated with a greater simplicity than the other kinds.

The Aravah reflects the service of the simple Jew, whose Torah study and performance of mitzvos lack both intellectual and emotional depth; they perform mitzvos out of simple faith, which is connected more with G-d’s simplicity.