Our Gemara on Amud Beis discusses the consequences of diverging from the formula that the sages instituted for process of divorce. Rabbi Meir has an opinion that once the Rabbis Instituted a particular process, even if details of the process are rabbinic in origin, a divorcement bill that does not in here to this process is rendered invalid. This is even to the extent that the divorce is ineffective, and a child from a subsequent union would be considered illegitimate. 

אִין רַבִּי מֵאִיר לְטַעְמֵיהּ דְּאָמַר רַב הַמְנוּנָא מִשְּׁמֵיהּ דְּעוּלָּא אוֹמֵר הָיָה רַבִּי מֵאִיר כָּל הַמְשַׁנֶּה מִמַּטְבֵּעַ שֶׁטָּבְעוּ חֲכָמִים בְּגִיטִּין יוֹצִיא וְהַוָּלָד מַמְזֵר 

The Gemara answers: Yes, as Rabbi Meir conforms to his own line of reasoning with regard to this issue. As Rav Hamnuna said in the name of Ulla: Rabbi Meir would say that in any case where one who deviates from the formula coined by the Sages with regard to bills of divorce, and the woman married despite this, the second husband must divorce the woman who married him on the basis of that bill of divorce, and the offspring is a mamzer.

However, the Chachamim do not have such a stringent requirement and do not invalidate the Get.

Based on other references in Shas (see Gittin 80b, Rashba, and Bava Metzia 55b) it seems that Rabbi Meir’s position is that as an extra stringency, the rabbis rendered the divorce invalid to strengthen respect for the enactment. Such are the powers of the rabbis when they deem it necessary. Nonetheless, the halakha is in accordance with the Chachamim that divorcement bill is not invalidated.

What is interesting about this is that we see Rabbi Meir in our Gemara taking a stringent position about enforcing the legal will and compliance of the rabbi to the point of invalidating a process that technically would be kosher, according to the strict biblical law. However, we find a contradictory discussion regarding the proper formula for blessings (Berachos 40b):

רָאָה פַּת וְאָמַר: ״כַּמָּה נָאָה פַּת זוֹ, בָּרוּךְ הַמָּקוֹם שֶׁבְּרָאָהּ״ — יָצָא. רָאָה תְּאֵנָה וְאָמַר ״כַּמָּה נָאָה תְּאֵנָה זוֹ, בָּרוּךְ הַמָּקוֹם שֶׁבְּרָאָהּ״ — יָצָא, דִּבְרֵי רַבִּי מֵאִיר. רַבִּי יוֹסֵי אוֹמֵר: כׇּל הַמְשַׁנֶּה מִמַּטְבֵּעַ שֶׁטָּבְעוּ חֲכָמִים בִּבְרָכוֹת — לֹא יָצָא יְדֵי חוֹבָתוֹ. 

One who saw bread and said: How pleasant is this bread, blessed is the Omnipresent Who created it, fulfilled his obligation to recite a blessing. One who saw a fig and said: How pleasant is this fig, blessed is the Omnipresent Who created it, fulfilled his obligation. This is the statement of Rabbi Meir. Rabbi Yosei says: One who deviates from the formula coined by the Sages in blessings, did not fulfill his obligation. 

In that situation, Rabbi Meir takes a less stringent position, and allows one to fulfill the blessing obligation, despite not following the formula that was enacted by the sages. Notably, the halakha is in accordance with Rabbi Yosei, and the blessing is invalid. So the normative halakhic position seems to enforce the stringency of the formula for blessings, but not for divorcement bills, and Rabbi Meir holds the opposite. He finds it necessary to enforce the formula by the divorce process, but allows for more flexibility post facto by blessings. How do we account for the difference?

On the surface, one might say that it is a case of apples and oranges. That is, Rabbi Meir might find it more important to pay attention to the dictates of a technical legal process, such as divorce, over something that is more in the heart such as prayer. On the other hand, Rabbi Yosei and the sages might take the opposite position. It is important to allow the woman to get divorced, and if one aspect was not done perfectly according to rabbinic will, we still will allow her divorce to be valid under certain circumstances. However, ignoring the Rabbinic will by a blessing which is a continuous and daily process can lead to a deterioration in the purposefully developed text of the prayer. I think this is especially understandable if we realize that in Rabbinic times, they were no printing presses, and it was expensive to have scrolls. The likelihood is that most of the prayers were memorized. Therefore, extra caution needed to be taken to preserve the traditional liturgy. On the other hand, a divorce is a one time process, and generally done by a rabbinical court. The likelihood of deterioration of the overall integrity of the law is minimal

While we are discussing possible, social and psychological concerns behind Rabbi Meir’s position, it is possible to see some degree of consistency with other notable positions of Rabbi Meir. For example, Rabbi Meir is known for his position that the signators of the witnesses on the divorcement bill, create the divorce, as opposed to the opinion of Rabbi Eliezer that holds the divorce is enacted via the witnesses observing the handing over of the bill (see Gittin 21b). In addition Rabbi Meir holds that a person does not say a statement, which if it becomes legally ineffective, is ignored. Rather, we reinterpret his words to allow his basic intention to be fulfilled. For example, in Nazir 9a we learn:

גְּמָ׳ ״הֲרֵינִי נָזִיר מִן הַגְּרוֹגְרוֹת וּמִן הַדְּבֵילָה״ — בֵּית שַׁמַּאי אוֹמְרִים: נָזִיר. וְאַמַּאי? ״מִכֹּל אֲשֶׁר יֵעָשֶׂה מִגֶּפֶן הַיַּיִן״ אָמַר רַחֲמָנָא! בֵּית שַׁמַּאי סָבְרִי לַהּ כְּרַבִּי מֵאִיר, דְּאָמַר: אֵין אָדָם מוֹצִיא דְּבָרָיו לְבַטָּלָה.

It is stated in the mishna that if one says: I am hereby a nazirite and therefore will refrain from dried figs and from cakes of dried figs, Beis Shammai say: He is a nazirite. The Gemara asks: But why? The Merciful One states in the Torah in the passage dealing with naziriteship: “From anything that is made of the grapevine…he shall not eat” (Numbers 6:4). In naziriteship, only the fruit of the vine is prohibited. The Gemara answers: Beis Shammai hold in accordance with the opinion of Rabbi Meir, who says: A person does not utter a statement for naught. In other words, if one utters a statement that cannot be fulfilled as stated, his statement is interpreted in a manner that renders it relevant. Here too, Beis Shammai say that he misspoke and actually intended to take a vow of naziriteship.

Additionally, another famous teaching of Rabbi Meir is that an unlikely scenario based on a minority of situation is still halakhically significant (Kiddushin 80a and Chulin 86a חייש למיעוטא). It would seem that Rabbi Meir’s general approach to halakha was to be more concerned about specific details, whether it is the actual written text of a divorcement bill, or a contract, or it is the words of a person and his intention, or even just recognizing minority patterns. In all these cases, Rabbi Meir gives more weight to words and technicalities than his disputants. Nevertheless, when it comes to blessings, apparently Rabbi Meir was less concerned about the formality, at least to the extent that he was not going to invalidate the prayer. Perhaps that is because when it comes to prayer, it is more a matter of the heart. As our sages teach, in Sanhedrin (106b);

ורב יהודה שליף מסאני ואתא מטרא ואנן צוחינן וליכא דמשגח בן אלא הקב"ה ליבא בעי דכתיב (שמואל א טז, ז) וה' יראה ללבב

When Rav Yehuda would remove one of his shoes the rain would immediately fall, whereas we cry out and no one notices us. Rather, the Holy One, Blessed be He, seeks the heart, and the barometer of greatness is devotion of the heart and not the amount of Torah that one studies, as it is written: “But the Lord looks on the heart” (I Samuel 16:7).