“וישא אהרן את ידו אל העם ויברכם וירד מעשת החטאת והעלה והשלמים” (ט כב)
From the word וישא Chazal explain (Sotah 38a) that when saying the pesukim of Birchas Kohanim, the Kohein has to raise his hands [nesias kapayim]. However, the poskim are divided as to whether he has to raise his hands even before making the brachah “Asher Kidshanu Bikdushaso shel Aharon” or only after it, before reciting the pesukim.
The Shulchan Aruch Harav (Orach Chaim 128 17) rules that raising the hands is done only after the brachah, because that is the ikkar of the mitzvah, and because the brachah of the mitzvah is always said before the mitzvah is done, therefore, he should not raise his hands before he made the birchas hamitzvah.
But Harav Nachman Kahana, the Rav of Spinka, noted (Orchos Chaim ibid 14, cited in Kaf Hachaim ibid 76) that sefer Pa’aneach Raza (Bamidbar 6 27) wrote that the mitzvah of Birchas Kohanim is reciting the pesukim of the brachah, and “raising hands is not part of the mtizvah,” and therefore, on the contrary, one should do so before reciting the brachah of the mitzvah, so that there is no hefsek between the brachah and the mitzvah. The Pa’aneach Raza brings proof of his view from the passuk (Tehillim 134:2) “Se’u yedeichem kodesh ubarchu es Hashem.” First “raise your hands,” and only afterwards, recite the brachah of “Asher Kidshanu Bikedushaso shel Aharon.”
The Binyan Ariel (Vol. II, Maseches Sotah) discusses this issue, and explains that the words of the Gemara (Sotah 39a) are an answer to the question of “bemah ha’arachta yamim?” And Rabi Eliezer ben Shamua replied: “I never raised my hands without a brachah.” Is this what the Tanna was proud of, that he fulfilled his obligation of the Birchas Hamitzvos? But in light of the above, we can explain his words simply, that he was proud of the fact that he was strict not even to raise his hands for Birchas Kohanim before reciting the birchas hamitzvah, because he thought that raising his hands is part of the mitzvah.
Aharon Motioned for the Nation to Have Kavanah
“וישא אהרן את ידו אל העם ויברכם וירד מעשת החטאת והעלה והשלמים” (ט כב)
Why did the passuk write the word ידו without the yud, in a way that it could sound that Aharon raised only one hand? The Netziv of Volozhin explained that indeed, the Torah intended to allude here that before Aharon raised his hands to bless the nation, he first raised one hand, and thus motioned to them that he was about to bless them and they should have kavanah in their hearts for his brachah. Because if not, they would not have known that he was about to bentch them and they would not have kavanah on his brachah.
The Netziv further explained that from this passuk that teaches us that before the brachah, Aharon alluded to Am Yisrael to have kavanah on his brachah, Chazal learn (Yerushalmi Megillah 4 8, and likewise ruled in Shulchan Aruch Orach Chaim 128 23) the halachah that when the Kohanim bless the nation, the ones being blessed need to have kavanah in their hearts on the brachah.
Shu”t Meishiv Davar, Vol. II, 91
