Rabbi Zeira once spied his colleague Rabbi Hiyya bar Abba finishing his prayer and then immediately praying again (B. Berachot 30b). Rabbi Zeira sought the reason for the strange behavior, himself analyzing the situation: "If you tell me that you repeated the prayers because you did not have the proper mind-set at the first attempt, we have a tradition from Rabbi Eliezer that a person should always assess himself before embarking on prayer; if he is able to concentrate he should pray, if he is unable to concentrate he should not pray!"
The commentators explain that lack of concentration during the first part of the Amida invalidates the entire Amida (Tosafot, 12th-14th centuries, France-Germany). Other authorities add that Modim - the prayer of thanksgiving - also requires full attentiveness, though there is a question as to whether a lack of meditation invalidates that prayer (Semak, 13th century, France cf. Agguda, 13th-14th centuries, Germany).
Rabbi Zeira was suggesting that if the issue was one of concentration during prayers, it should have been resolved before Rabbi Hiyya bar Abba began praying, thus that could not be the reason for repeating the Amida.
Having dismissed that first possibility, Rabbi Zeira moved on to a second scenario: "Perhaps you omitted the special addition for Rosh Hodesh (new month), and therefore repeated the Amida." Rabbi Zeira quickly rejected this reason, citing a teaching dating back to the Second Temple period: If one mistakenly did not mention Rosh Hodesh in the Arvit evening prayer, there is no need to repeat the Amida for he can recite the addition the following morning in the Shaharit prayer. If he forgot in Shaharit, he need not repeat the prayer for he will reference Rosh Hodesh in the additional Musaf prayer, which by its nature makes mention of the date. If instead of the Rosh Hodesh text for the Musaf prayer, he recited a regular Amida and neglected to mention the auspicious day, he need not recite Musaf again for he still has the opportunity to mention Rosh Hodesh in the afternoon Minha prayer.
Relying on this teaching Rabbi Zeira concluded that there was no reason for Rabbi Hiyya bar Abba to repeat the Amida, unless he was praying Minha, a possibility not entertained.
It was now Rabbi Hiyya bar Abba's turn to explain his actions: "Indeed I forgot the Rosh Hodesh addition and this precipitated my repetition of the Amida. And with regard to the teaching you cited - this tradition was said only in regard to a congregation. I, who was praying alone, was required to repeat the Amida."
What are the congregational circumstances that do not require a repetition following an omission? Commentators offer two possibilities: According to one approach, when praying with a congregation the special Rosh Hodesh addition will be recited by the leader of the service in the Amida repetition. Hence the individual is not required to repeat the silent Amida for he will hear it in the public repetition. When praying alone, however, though there will be other opportunities to recite the Rosh Hodesh addition, for that particular prayer it was omitted entirely and hence the Amida must be repeated (Rashi, 11th century, France).
A second approach suggests that the tradition is not referring to individual congregants but to the leader. The leader need not repeat his silent Amida if he omitted the Rosh Hodesh addition, for such a requirement would constitute an unnecessary burden on the congregation. Hence we rely on the fact that he will mention Rosh Hodesh in the repetition. Someone praying alone, however, must always repeat the Amida if he omits the Rosh Hodesh addition, and this was the case of Rabbi Hiyya bar Abba (Behag, ninth century?, Babylonia).
The Talmud offers a second discussion about one who omits any mention of Rosh Hodesh. According to this passage, forgetting the Rosh Hodesh addition in the Arvit prayer never obligates a repetition. Not so one who slips in Shaharit or Minha. The basis of this distinction is that in Temple times, before the calendar was fixed, the court would publicly declare a new month based on the testimony of witnesses who saw the new moon. This process never occurred at night and hence an Arvit omission does not necessitate an Amida repetition.
A difference is apparent between the two exchanges: The concerns of the first passage are the opportunity to mention Rosh Hodesh in subsequent prayers and the difference between an individual and a congregation. The second passage spotlights the time for declaring the new month as the determining factor in questions of repetition. The different foci give rise to different normative possibilities.
Halacha adopts the second exchange and differentiates between an omission in Arvit and an omission in Shaharit or Minha (Shulhan Aruch OH 422 and commentators).
Though normative law prefers the second passage, there is still much to be harvested from the first. Let us return to Rabbi Zeira's first assumption and the tradition he quoted: Before prayer a person should always assess whether he is sufficiently focused. One of the hassidic masters of our generation, the Penei Menahem of Gur (1926-1996), related that a rosh yeshiva (head of a talmudic academy) once complained that the students' learning smacked of superficiality. When he wished to explain how serious the problem was, he used the term daven - the Yiddish expression for prayer: "They daven up a few pages of Talmud!" he grumbled.
The Penei Menahem was dismayed at this description: Should we conclude that praying is to be done cursorily and only learning needs to be a conscious endeavor? The opposite seems to be true, for the Talmud permits superficial study: "A person should always recite Talmud, even if quickly forgets what he has learned, even if he does not understand what he is saying" (B. Avoda Zara 19a). While with regard to prayer - as we have seen above - one who cannot concentrate is instructed to tarry until he is able to focus. Thus the Penei Menahem concluded: It is prayer that requires an attentive heart and conscientious approach.
The writer is on the faculty of Pardes Institute of Jewish Studies and is a rabbi in Tzur Hadassah.