In this week’s Parsha, Naso, the Torah records the Mitzvah of Birkat Kohanim (the Priestly Blessing). Hashem says, כה תברכו את בני ישראל “…so shall you bless Bnai Yisrael...” (6:23). The Gemara (Ketubot 24b) extracts that this command applies only to Kohanim, that a “Zar” (non-Kohen) violates an Issur Asai by making the Priestly Blessing (see Rashi there). The Rama codifies this rule as a normative Halacha.
However, in Masechet Shabbat (118b) the Gemara relates a story in which R’ Yosi says that never had he disobeyed the words of his friends. He took this to such an extent that although he knew that he was not a Kohen, he would have gone to the Duchan (platform) in order to make the priestly blessing, had his friends asked him to. This story is quite perplexing in light of the aforementioned Halacha. In fact, Tosafot asks how R’ Yosi could have possibly done this and how his friends could have allowed him to. The ר"י answers that there really is no Halachic problem with making the priestly blessing other than perhaps a “Beracha Levatala.” This answer is contradictory to what has been stated earlier and so the question still demands an answer.
The Torah Temima presents an interesting answer. He cites a Girsa, in the text of the Gemara (cited by Rabbeinu Yerucham), which indicates that Kehuna was not the issue but rather that R’ Yosi thought that he was not a “Kedai” (worthwhile) person. And when R’ Yosi said that he would have gone up to the Duchan, according to the Torah Temima, he was not referring to the platform of the Kohanim, rather he was referring to any pulpit from which he could make a speech. According to the Torah Temima’s reading of this story, R’ Yosi’s friends asked him to speak to the crowd, and although he knew himself that he was not sufficient or good enough to give the speech, he did.