MB 4: And after it - Even though many authorities take the view that [recital] of the first paragraph is a Torah law and the second one a Rabbinical enactment, and there are those who hold that only the very first verse [of the first paragraph] is a Torah law, and most certainly according to all views the Blessings are Rabbinical so when in doubt there ought to be no need to repeat them, we can explain that this is the way our Rabbis instituted [the blessings for the Shema], that whenever one reads the Shema he should read it with the Blessings, unless they specifically permitted their omission e.g. see the Rama in Siman 106:3.
It would seem that if he knew that he said the first verse or the first paragraph, ie he said that which is Torah Law according to each of the different views [above] and he is only in doubt about the rest, that he need not repeat it. However, in Siman 64:3-4 it appears that one should repeat it - this must have been the original institution, to repeat it. Where one is in doubt if he said the third paragraph and "Emes V'Yatziv" [the following blessing, 'It is true and correct'], then he must repeat it because all agree that mentioning the Exodus is a Torah law. [The third paragraph of the Shema incorporates the Mitzvah of Wearing Tzitzis on a four cornered garment as well as the Mitzvah of Remembering the Exodus of Egypt. -- JC] However there are various opinions about this as well. Some say that one should say the third paragraph and also 'It is true and correct', because it is all one item. Others say that he should just say the third paragraph and thereby fulfill his Torah obligation, and he need not say 'It is true and correct' - and so agreed the Shaagas Aryeh.
The Shaagas Aryeh also wrote that if this doubt occurred in the evening, when one does not know if he said the third paragraph and "Emes V'Emunah" [the first blessing following the Evening Shema, 'It is true and faithful'], then he should repeat 'It is true and faithful' and he need not repeat the third paragraph of the Shema. [There is no obligation to wear Tzitzis at night - JC]. If he is certain that he said all three paragraphs and is only in doubt about 'It is true and correct' in the morning or 'It is true and faithful' in the evening, then the rule is the same in both cases: that he need not repeat it. This is because since he said the third paragraph and thus made mention of the Exodus, according to all views the blessing is merely Rabbinical.
MB 5: But - because it is only Rabbinical, even the blessing of 'It is true and correct' [because he mentioned the Exodus from Egypt during the third paragraph of the Shema], and when in doubt concerning a Rabbinic enactment we are lenient. If one knew he had said 'It is true and correct', but didn't remember if he had said the Shema, the Elya Rabbah holds that he need not repeat it. There is also proof to this from Siman 64:4 [where we say that one must have said the previous words if one is now at a certain point], and look in the Pri Megadim.
Jonathan Chody jonathan@quantime.co.uk
In view of the terrorist bombing in Tel Aviv and the deaths of the Israeli soldiers, I feel compelled to dedicate my contribution to today's Halacha Yomi to the memory of the victims, who died sanctifying the Name of G-d (Al Kiddush HaShem), since they were killed merely because they were Jews. Lawton Cooper