Siddur

A siddur (Hebrew: סדור‎‎ [siˈduʁ]; plural siddurim סדורים, [siduˈʁim]) is a Jewish prayer book, containing a set order of daily prayers. The word siddur comes from the Hebrew root Hebrew: סד״ר‎‎ meaning "order".

The earliest parts of Jewish prayer book are the Shema Yisrael ("Hear O Israel") (Deuteronomy 6:4 et seq), and the Priestly Blessing (Numbers 6:24-26), which are in the Torah. A set of eighteen (currently nineteen) blessings called the Shemoneh Esreh or the Amidah (Hebrew, "standing [prayer]"), is traditionally ascribed to the Great Assembly in the time of Ezra, at the end of the Biblical period.

The name Shemoneh Esreh, literally "eighteen", is a historical anachronism, since it now contains nineteen blessings. It was only near the end of the Second Temple period that the eighteen prayers of the weekday Amidah became standardized. Even at that time their precise wording and order was not yet fixed, and varied from locale to locale. Many modern scholars believe that parts of the Amidah came from the Hebrew apocryphal work Ben Sira.

According to the Talmud, soon after the destruction of the Temple in Jerusalem a formal version of the Amidah was adopted at a rabbinical council in Yavne, under the leadership of Rabban Gamaliel II and his colleagues. However, the precise wording was still left open. The order, general ideas, opening and closing lines were fixed. Most of the wording was left to the individual reader. It was not until several centuries later that the prayers began to be formally fixed. By the Middle Ages the texts of the prayers were nearly fixed, and in the form in which they are still used today.

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