By Rabbi Berach Steinfeld
The posuk in Bamidbar 6:23 says that Hashem commanded Aharon
There are a number of answers to this question. The first answer is based on Sotah 38b that we only give a kos of a bracha to one who is a tov ayin as the Maharsha explains that the kavana of the mevarech goes into the bracha. That is why Hashem chose the Kohanim. The Kohanim have no chelek in Eretz Yisroel so they can give the bracha whole-heartedly, without any misgivings. A second tirutz is that since the Kohanim are the ones bringing korbanos, which bring a kapara for every Yid, it is therefore fitting that they are the mevarchim. In a similar vein, we can answer that Kohanim are considered the shaliach of Klal Yisroel
The sefer Minchas Shmuel discusses the fact that part of the bracha uses the terminology “Koi sevarchu.” The word Koi is b’gematria 25. The Kohanim received the chof daled (24) matnos Kehuna. The twenty-fifth matana they received was that they are the ones to bentch Klal Yisroel. A sixth tirutz is that since the Kohanim never sinned regarding the Eigel, it is only fitting that they should be the defenders of Klal YIsroel and therefore be able to bring bracha unto Klal Yisroel. A seventh tirutz is similar to the Kli Yakar’s explanation as to why the Kohanim were appointed to see the tzoraas even though talmidei chachamim were known to be the ones who would not veer from halacha, neither to the right or left. The Kohanim were known as rodef shalom and had the great quality of being humble. They were therefore in a position to pasken negaim and for that same reason, they were the ones chosen to bentch Klal Yisroel.
The eighth and final answer is that the bracha of the Kohanim does not come from the Kohein himself; the Kohein is just the vehicle of the bracha. The Rambam Hilchos Tefillah 16:6,7 says that even a Kohen who is not so medakdek be’mitzvos can and should duchen and bentch Klal Yisroel. The bracha is from Hashem, and the Kohein is just the shaliach. A bracha of a tzaddik can be understood as “Tzaddik gozer ve’Hakadosh Baruch Hu mekayem.” The bracha of the tzaddik may not end up being the one that Hashem intended to give. Conversely, when a Kohein gives a bracha it will always reflect Hashem’s will. We therefore want the bracha of the Kohanim!
May we be zocheh to be gebentched from Hashem via the Kohanim in the Bais Hamikdash!
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