The following question on Mi Yodeya, about parashat Yitro:
I think that one can put forth the following points.
Look at the context. By this, I mean look at the other Rashis in the perek, and see how many of them are from the Mechilta. See this in Mekorei Rashi, or alternatively, from Chabad's Tanach. A taste:
What Rashi is doing in this perek is a running commentary, primarily adapted from the Mechilta. He is channeling the Mechilta for us. As such, if Mechilta has a comment of the sort Rashi would bring (uleaggada hameyashevet divrei hamikra), we would expect him to bring it, even if elsewhere, in a gemara somewhere, there is a dispute, and we rule against the position.
Further, this is not the only place Rashi brings a midrash halacha which is against the paskened halacha. Some modern meforshei Rashi take note of this, and explain that Rashi will bring forth such a midrash if he feels that it is more along the lines of peshat, since his goal is a peshat-oriented commentary, as adopted / adapted from midrash. So indeed, Rashi can and will cite midrash which will be against decided halacha, on occasion.
There are some good answers there, especially this one:On the Posuk "Zochor Es Yom HaShabos L'Kadsho", Rashi saysתנו לב לזכור תמיד את יום השבת שאם נזדמן לו חלק יפה יהא מזמינו לשבת (Take heart to remember the Shabbos - if you find something nice place it aside for Shabbos).Rashi's source seems to be Beitzah 16. However the Gemora there records an argument between Bais Hillel and Bais Shamai how to prepare for Shabbos. Given that we rule according to Bais Hillel, why is Rashi here quoting according to Bais Shamai?
I've heard from Rabbi Shalom Carmy that the reference to Beitzah is actually a printer's error and Rashi got this from this Mechilta D'Rabbi Yishmael, where it remains undisputed.Rashi didn't give a source, and it was the printer's perogative to give any and all sources he felt like. But say it is Mechilta. As a commenter at Mi Yodeya asks, how does that help? Isn't it still against Halacha, meaning like Bet Shammai instead of like Bet Hillel?
I think that one can put forth the following points.
Look at the context. By this, I mean look at the other Rashis in the perek, and see how many of them are from the Mechilta. See this in Mekorei Rashi, or alternatively, from Chabad's Tanach. A taste:
1. God spoke all these words, to respond: | א. וַיְדַבֵּר אֱלֹהִים אֵת כָּל הַדְּבָרִים הָאֵלֶּה לֵאמֹר: | |
God spoke: Heb. אֱלֹהִים. [The word] אֱֱלֹהִים always means “a judge.” [This Divine Name is used here] because there are some sections in the Torah [that contain commandments] that if a person performs them, he receives a reward, but if not, he does not receive any punishment for them. I might think that so it is with the Ten Commandments. Therefore, Scripture says: “God (אֱלֹהִים) spoke,” [signifying God’s role as] a Judge, [Whose function is] to mete out punishment [when the Ten Commandments are not obeyed]. [from Mechilta] | וידבר א-להים: אין א-להים אלא דיין. לפי שיש פרשיות בתורה שאם עשאן אדם מקבל שכר, ואם לאו אינו מקבל עליהם פורענות, יכול אף עשרת הדברות כן, תלמוד לומר וידבר א-להים, דיין ליפרע: | |
all these words: [This] teaches [us] that the Holy One, blessed be He, said the Ten Commandments in one utterance, something that is impossible for a human being to say [in a similar way]. If so, why does the Torah say again, “I am [the Lord, your God (verse 2)]” and “You shall have no…” (verse 3)? Because He later explained each statement [of the Ten Commandments] individually. — [from Mechilta] | את כל הדברים האלה: מלמד שאמר הקב"ה עשרת הדברות בדבור אחד, מה שאי אפשר לאדם לומר כן. אם כן מה תלמוד לומר עוד אנכי ולא יהיה לך, שחזר ופירש על כל דבור ודבור בפני עצמו: | |
to respond: Heb. לֵאמֹר, lit., to say. [This] teaches [us] that they responded to the positive [commandments], “Yes,” and to the negative [commandments], “No.” -[from Mechilta] | לאמר: מלמד שהיו עונין על הן הן ועל לאו לאו: |
What Rashi is doing in this perek is a running commentary, primarily adapted from the Mechilta. He is channeling the Mechilta for us. As such, if Mechilta has a comment of the sort Rashi would bring (uleaggada hameyashevet divrei hamikra), we would expect him to bring it, even if elsewhere, in a gemara somewhere, there is a dispute, and we rule against the position.
Further, this is not the only place Rashi brings a midrash halacha which is against the paskened halacha. Some modern meforshei Rashi take note of this, and explain that Rashi will bring forth such a midrash if he feels that it is more along the lines of peshat, since his goal is a peshat-oriented commentary, as adopted / adapted from midrash. So indeed, Rashi can and will cite midrash which will be against decided halacha, on occasion.