Birkat Kohanim at a late Musaf

Question

Generally speaking, Birkat Kohanim can/is done at any daytime prayer. We do not do so at mincha because in the afternoon people have already eaten and the kohanim may have drunk some alcohol which would invalidate them from performing their duty.

Musaf is usually prayed in the morning after Shacharit; however, one is permitted to pray Musaf lechatchila until the end of the seventh hour, and bedieved all day.

My question is, do the kohanim perform Birkat Kohanim at Musaf if it is being prayed after noon? What if it is being prayed after Mincha?

Finally, if the answer to the above is No, does that affect saying Sim Shalom vs Shalom Rav in the individual's Shmoneh Esrei? Generally speaking, we (Nusach Ashkenaz) only say Sim Shalom at a prayer where Birkat Kohanim could be said.

Answer 1

It seems from the language of the Shulchan Aruch 129:1 that the omission is dependent on the mincha service, not the time.

In addition to shacharis, musaf and neilah, the SA allows bircas kohanim at mincha on a fast day based on 2 factors. Firstly, the custom [was] to daven late on fast days and so the mincha service takes on a similarity to a neila service. Secondly, it will not be confused with mincha of other days since there is no drinking. (See seif 2 to understand how the SA implies a second factor and the reasoning behind it.)

If the time of day is what allows or disallows bircas kohanim, the SA should have said the following: Normally at late mincha we do not allow bircas kohanim even though drinking is uncommon, because one will confuse it with other minchas. But no one will confuse a fast day since there is no drinking. Why does the SA need to compare late mincha to neila?

Apparently, what allows or disallows bircas kohanim is the service, mincha, which is commonly done during drinking hours. That is why mincha on a fast day needed to be re-categorized as a quasi-neila (but is still mincha enough to cause confusion if it weren't a fast day thereby requiring factor #2).

Accordingly, there would be bircas kohanim in late musaf.

Answer 2

I have been in many Shuls where Musaf was first being said after noon and they still said Birchas Kohanim. Although I have no other source it makes sense to me at least that so long there was no Kiddush break there should be no problem with saying Birchas Kohanim at a late Musaf.