Shabbat Morning Kiddush
Question
Is it ok to just say "al ken berach..." for the Shabbos day kiddush?
Answer
Shalom!
Thank you for your question!
As you clearly realize, most people begin the Shabbat morning Kiddush with the verses “ v’shamru Bnei Yisrael et haShabb at ” or from “ zachor et yom haShabbat l’kadsho .” Nevertheless , there is a somewhat widespread practice to merely say “ al ken berach Hashem et yom haShabbat va’yekadshehu ” followed by the borei pri hagefen on wine.
This “short Kiddush” is problematic owing to the ban against dividing or even reciting part verses in ways that do not appear in the Torah and “al ken…” is only a partial verse, not a whole one.
Nevertheless, some authorities, primarily Chassidic ones, justify using this short Kiddush for a numner of reasons. One explanation is that the ban on reciting a partial verse only applies when one is halachically required to recite the entire verse. The Shabbat morning Kiddush, however, doesn’t require any verses at all. It merely requires a “borei pri hagefen” on wine. All the Kiddush verses recited are essentially a matter of custom.
Another justification for he short Kiddush is that the ban on reciting a partial verse only applies if one intends to combine it with other incomplete verses. According to this approach, it is permitted to recite a partial verse in the context of a prayer or other non-halachic matter.
It is also noted that although the “ al ken berach…” formula is an incomplete verse, it begins after a word, in that very same verse, that is read with the “ etnachta” tune. This is significant because the etnachta tune signifies a pause or conclusion of a thought while the words that follow the etnachta are considered to be a new thought or theme. In other words, it is permitted to use the “al ken berach…: since it is essentially an independent thought and theme.
The above discussion is merely to help you understand how some authorities have justified the “al ken berach…” short Kiddush. However, those who do not have this custom of simply saying “al ken berach…” should not begin doing so.
Source
Berachot 14a; Ta’anit 27b; Megilla 22a; OC 289:1;
Mishna
Berura
289:2,20; Aruch
Hashulchan, OC 289:3