The ד׳ מינין are מעכבין זה את זה, yet it is the אתרוג and the לולב that are especially cherished, while the ערבה is generally considered secondary, even though on הושענה רבה the מצוה is performed with the ערבה exclusively. Indeed, when it’s all over, the ערבות are knocked to the ground, stepped on, and thrown away. ר׳ יחזקאל בנעטה explained that the אתרוג and לולב are cherished because they come from far away, while the ערבות are found locally and this is the way of the world, the guest from afar is honored and the one who comes from nearby is considered less חשוב.
05/07/2020