During Birchas Kohanim, before the Kohanim answer the last part of each Brocha, the congregation says a Tefilla titled Yehi Ratzon. (Before the last Brocha from the Kohanim the Tefilla starts Ribono Shel Olam.) As far as I know these passages are only said on a weekday & not on Shabbos. What is the source for the Congregation not to say the Yehi Ratzon in Birchas Kohanim when Yom Tov falls out on Shabbos?
Kirzur Shulchan Aruch סימן ק - הלכות נשיאת כפים - עוֹד נוֹהֲגִין בִּמְדִינוֹתֵינוּ, שֶׁבְּיוֹם טוֹב שֶׁחָל לִהְיוֹת בַּשַׁבָּת, אֵין נְשִׂיאַת כַּפַּיִם, אֶלָּא בְּיוֹם הַכִּפּוּרִים, שֶׁאֲפִלּוּ חָל בַּשַׁבָּת, נוֹשְׂאִין כַּפֵּיהֶם. וְיֵשׁ מְקוֹמוֹת שֶׁנוֹהֲגִין שֶׁבְּכָל יוֹם טוֹב, אֲפִלּוּ חָל בַּשַׁבָּת, נוֹשְׂאִין כַּפֵּיהֶם, וְכֵן נָכוֹן יוֹתֵר.– Danny SchoemannApr 24, 2017 at 8:35
I think you mixed up R.S.O. and Yehi Ratzon - the Y.R. is the last one. In any case, why ask only about Yehi Ratzon - the custom is not to say either of them on Shabbos?– JayApr 24, 2017 at 13:20
You are correct, I meant to ask from both paragraphs. Perhaps in light of the above Halacha brought by @DannySchoemann from the Kitzur Shulchan Aruch who brings a difference of opinion whether we should even be saying Birchas Kohanim on Shabbos, we take a middle ground by saying Birchas Kohanim but not the passages in between the Brachos.– EarlApr 24, 2017 at 14:07
2Depends what the reason is. My guess would be that it more likely has something to do with the fact that we generally don't make personal requests on Shabbos.– JayApr 24, 2017 at 14:20
1@Jay We also generally don't make personal requests on Yom Tov. That's why we cut out most of the requests from the Amida on those days (note as well C). Indeed the Gra opposed the recitation of the dream paragraphs on Yom Tov as well hebrewbooks.org/pdfpager.aspx?req=1478&pgnum=18 . Of course the way it's commonly done nowadays with the extended singing is anyway incredibly problematic due to Hefsek judaism.stackexchange.com/a/20392/759– Double AA ♦Apr 24, 2017 at 17:18
The Magen Avrohom (128:70) suggests that a reason not to say Birchas Kohanim at all on Shabbos would be because on Shabbos we don't make personal requests such as these related to dreams, whereas on Yom Tov we are more lenient in this regard, just as we are more lenient on Yom Tov than on Shabbos regarding saying the Avinu Malkeinu prayer.
ובקצת מקומות נוהגין כשחל שבת בי"ט שאין נ"כ ולא ידעתי טעם לדבר ואפשר משום שאומרים רבש"ע וכו' ויש בו איסור תחנה בשבת משא"כ בי"ט דלא קפדי כולי האי כמ"ש בא"מ שא"א בשבת
We can further speculate that even those places that do say Birchas Kohanim on Shabbos might for that reason still avoid these personal requests on Shabbos.
1Worth noting that the distinction between Shabbat and Yom Tov regarding personal requests is not at all universally held, and even among those who do think Yom Tov is more lenient, that is generally only regarding requests related to nature of the holiday (eg. Avinu Malkenu on Rosh haShana, or various Piyutim in the prayers such as Geshem). Indeed the Gra reportedly opposed saying the dream-request even on Yom Tov, just as we omit general requests from the Shemoneh Esrei.– Double AA ♦Apr 24, 2017 at 21:39