The Times of Keriat Shema
The previous shiur addressed the question of the time periods which frame the mitzva of keriat shema. Is the mitzva defined by classic periods of evening and morning, or is the mitzva framed by the periods during which people get up and retire? This question applies equally to morning and evening, and it may impact the precise moment at which the mitzva commences. This shiur will explore two associated positions of Rabbeinu Tam regarding the timing of keriat shema. These dual opinions may indicate that Rabbeinu Tam views keriat shema as dependent upon classical periods of night and day and not upon more unique situations of awakening and retiring.
Rashi, in his commentary to the very first mishna of Berakhot (2a s.v. Ad), questions the validity of shema recited before tzeit ha-kokhavim (when the stars come out). Based upon the simple reading of the first mishna (as outlined in the previous shiur), shema may only be read after tzeit. This would seriously affect communities who recite arvit prior to tzeit in the summer. Rashi concludes that keriat shema she-al ha-mitta, the recitation of the first paragraph in one's bed, must constitute a fulfillment of the mitzva as shema is definitely recited after tzeit in this context.
Rashi's position unleashes a storm of controversy both logical and empirical. After all, bedside shema lacks the standard berakhot of shema. Furthermore, it is presented by the gemara as a safeguard against nighttime dangers; it does not seem like the type of recitation which would constitute fulfillment of the actual mitzva of keriat shema. Empirically, the custom to recite arvit prior to tzeit in the summer (particularly on erev Shabbat) is extremely prevalent, and dismissing its validity seems very strident.
Rabbeinu Tam (ibid. s.v. Mei-eimatai) defends the practice by citing Rabbi Yehuda's position (ibid. 26a) that arvit can actually be recited from pelag ha-mincha onwards (when approximately one-tenth of the daylight time is left). As the evening prayer can be recited during this period, it is evidently considered the start of halakhic evening (at least for tefilla and its associated components, of which shema is one). If night has already commenced, then the evening shema may already be recited.
It seems as if Rabbeinu Tam defines shema as dependent upon the halakhic onset of evening according to Rabbi Yehuda and less attentive to the period of retiring. It would seem very illogical to stretch Devarim 6:7's "be-shakhbekha" (beginning the process of sleep) to an hour and a quarter BEFORE sunset.
A second position of Rabbeinu Tam which seems to confirm this view of keriat shema relates to the recitation of shema in the morning. The gemara in Berakhot (9b) cites several different opinions about the time at which the mitzva to recite shema in the morning commences. Ultimately, the gemara cites the opinion of Abbayei that keriat shema should ideally be recited "like the vatikin" who recite shema immediately prior to hanetz ha-chama (sunrise) in order to begin the amida at the precise moment that the sun emerges above the horizon. This yields a position which views the period of keriat shema as beginning prior to actual sunrise, the standard start of the day throughout Halakha. Rabbeinu Tam disagrees, claiming that for keriat shema just as for all other areas of Halakha the day begins at hanetz ha-chama. In fact, vatikin though zealous and devout- recite shema during an inappropriate time and do not fulfill the mitzva of morning shema! This position of Rabbeinu Tam seems consistent with his aforementioned position about keriat shema at night. He believes that shema is a product of formal evening and day; shema at night may be recited during halakhic evening, even though no one has yet begun to go to sleep. However, in the morning, shema must be recited only AFTER sunrise, since only then does the halakhic day actually begin.
It is perhaps this very question that animates an intriguing machaloket between the Ba'al Ha-ma'or and the Ramban. The gemara in Berakhot (8b) cites two opinions of Rabbi Shimon bar Yochai about the period between dawn and sunrise (after alot ha-shachar and before hanetz ha-chama). According to his first opinion, shema of the morning may be recited during this period, while according to his second opinion, it is shema of the evening which may be recited. Being that he is the author of each position and the Gemara never questions this seeming contradiction, the Rif rules in accordance with BOTH statements - effectively allowing keriat shema of BOTH the evening AND the morning to be recited during this single halakhic period. The Ba'al Ha-ma'or flatly rejects this notion, ultimately ruling in accordance with Rabbeinu Tam that shema of the morning may only be recited AFTER sunrise. The Ramban defends the
Logically, the Ba'al Ha-ma'or's position would see the mitzva of keriat shema as based upon classic definitions of night and day. Obviously, a distinct period is defined as EITHER night OR day but not both. Therefore a period cannot accommodate the recitation of the shema of both the morning and the evening. By contrast, the Ramban and