I've noticed that Ashkenazi synagogues pronounce some words differently than Sefardi synagogues. What is the halachic status of these two variants? Do Ashkenazim who speak "Israeli" on a daily basis act consistently if they use a different pronunciation only for prayers?
The Aish Rabbi Replies
Today there are two forms of Hebrew pronunciation. One is "Israeli/Sefardi" pronunciation which is characterized by all tavs said as "t" and the kamatz vowel pronounced as "a." The second is "Ashkenazi," typified by the "s" sound of the unpointed tav and the kamatz pronounced as "o." A typical example is whether to say Shabbat or Shabbos.
Every Jew has a tradition/custom of how to act. This includes many aspects of Judaism including dress, text of prayers, and pronunciation. Each Jew has to follow his/her traditions and customs. Indeed, the Talmud says that the Jewish people were redeemed from Egypt because they didn't change clothes, names and language!
In the last century, when spoken Hebrew became revived in Israel as a modern language, Sefardi pronunciation became adopted as the prevailing style for business, conversation, etc. Let's clarify: Your question is not an issue of modern spoken Hebrew. That is defined solely by Israeli street, which uses "Hebraicized" words such as "telephone" and "food processor."
The halachic issue is that some Ashkenazi Jews switched over to this pronunciation for prayers as well. This is very difficult to support. Many authorities maintain that an Ashkenazi who pronounces the name of God (Aleph, Daled, Nun and Yud) in the "Israeli" way has not fulfilled his obligation. This applies when saying blessings, praying, or a public Torah reading. For example, when saying the Shema twice daily, the halacha demands one to pronounce every letter of the Shema perfectly. Switching to Sefardi pronunciation would be problematic in this regard. (Mishnah Berurah 68:4; Shu"t Minchat Yitzhak 3:9)
If you are Ashkenazi and grew up learning only the Sefardi pronunciation, I realize that it is difficult to adjust to the Ashkenazi way when saying prayers. Many have done so successfully, and as an aid you may want to mark a red dot in your Siddur in the places where you need to remember to pronounce correctly.
Let me add that when praying in a synagogue that is different from your own customs, you should follow what the custom of the synagogue in anything that is said aloud. That means you should recite Kedusha, Kaddish and even an aliyah to Torah the same as they do. Regarding the silent Shemoneh Esrei, however, which is not "public," you should pray your own text and pronunciation.