Eruvin Daf 13 עירובין דַף 13

There is a machlokes in a Baraisa regarding putting kankantom into ink, which makes it impossible to completely erase the ink, in order to write the parsha of Sotah in a sefer Torah.

Rebbe Yehuda said that Rebbe Meir used to say, that one may put kankantom into ink for writing a sefer Torah, except for the parsha of Sotah. Rebbe Yaakov said in Rebbe Meir’s name that it may be used to write the parsha of Sotah as well, but not  for writing the parsha of Sotah that was used in the Beis Hamikdash for the Sotah waters.

Rebbe Yirmiyah said that the practical difference between them is whether it is valid to erase the pesukim from a regular Sefer Torah in the bitter waters of the Sotah. In order for pesukim to be valid to be used for the bitter water that a Sotah must drink, it must be words that are able to be erased. Therefore, according to Rebbe Yehudah, who holds that the pesukim from a regular sefer Torah are valid to be used to be put inside the Sotah waters, one cannot put kankantom in the ink. According to Rebbe Yaakov, however, they are not valid, and therefore the pesukim of a regular sefer Torah may be written with ink that has kankantom in it. Only the parsha of Sotah that was used within the Beis Hamikdash, may be used. Therefore, it is only these pesukim that may not be written with kankantom.

Rebbe Meir was a talmid of both Rebbe Yishmael and Rebbe Akiva. The Gemara explains that he was originally a talmid of Rebbe Akiva but he was not able to discern his final psak, given Rebbe Akiva’s ability to defend both sides of a position. He went to learn by Rebbe Yishmael וגמר גמרא - to learn the various traditions and then went to Rebbe Akiva וסבר סברא - and he studied them with great analysis .

Rebbe Acha bar Chanina said that there was none in the generation like Rebbe Meir but they did not fix the halachah like him because his chaveirim could not fathom the depths of his reasoning, for he could assert effectively that something tamei was tahor and vice versa. 

Rebbe said that the reason that he was sharper than his chaveirim is that he saw Rebbe Meir from behind, and if he had seen the front of him he would be even sharper.

The Gemara asks why Beis Hillel merited to have the halachah fixed according to their view, and answers:
1. מפני שנוחין ועלובין היו – because they were agreeable and forbearing, showing restraint when challenged

2. ושונין דבריהן ודברי בית שמאי - and they would study their opinion and the opinion of Beis Shammai. Rashi explains that they would make great effort to show how the psukim that Beis Shammai brought as proofs could be understood differently.
3.  ולא עוד אלא שמקדימין דברי בית שמאי לדבריהן – and not only that, but they would even quote the words of Beis Shammai before their own.

תניא רבי יהודה אומר ר"מ היה אומר לכל מטילין קנקנתום לתוך הדיו חוץ מפרשת סוטה. ורב יעקב אומר משמו חוץ מפרשת סוטה שבמקדש. אמר רב ירמיה למחוק לה מן התורה איכא בינייהו כלומר לרבי יהודה מוחקין לה מן התורה ולכן קנקתום אסור לפרשת סוטה שבתורה ולרב יעקב אין מוחקין לה מן התורה

רבי מאיר היה לומד מתחילה אצל ר"ע ומדלא מצי למיקם אליביה אתא לקמיה דרבי ישמעאל וגמר גמרא והדר אתא לקמיה דר"ע וסבר סברא א"ר אחא בר חנינא גלוי וידוע לפני מי שאמר והיה העולם שאין בדורו של רבי מאיר כמותו ומפני מה לא קבעו הלכה כמותו שלא יכלו חבירו לעמוד על סוף דעתו שהוא אומר על טמא טהור ומראה לו פנים על טהור טמא ומראה לו פנים אמר רבי האי דמחדדנא מחבראי דחיזתי לר"מ מאחרויה ואילו חזיתיה מקמיה הוה מחדדנא טפי דכתיב והיו עיניך רואות את מוריך

מפני שנוחין ועלובין היו ושונין דבריהן ודברי בית שמאי

ולא עוד אלא שמקדימין דברי בית שמאי לדבריהן