(Mishnah-R. Meir): If the 14th of Nisan falls out on Shabbos, one must destroy everything before Shabbos.

(Chachamim): [It is destroyed] at the correct time.

(R. Eliezer b'r Tzadok): Terumah is burned before Shabbos and Chulin is burned at the correct time.

(Gemara): R. Meir follows the opinion of R. Eliezer but is more stringent, as R. Eliezer is stringent in order to avoid a definite case of Bal Yera'eh and Bal Yimatzei; R. Meir is stringent in order to avoid a possible case of Bal Year'eh and Bal Yimatzei.

Rabanan follow the opinion of R. Yehoshua but are more stringent, as R. Yehoshua says that one may not burn Kodshim on Yom Tov and Rabanan say that may one not even burn Kodshim on Erev Shabbos (as they could be eaten instead).

(Beraisa - R. Yehuda): Both Beis Shammai and Beis Hillel agree that one may not burn Tahor Terumah (on the 13th if the 14th occurs on Shabbos) and that one may burn Tamei Terumah; they disagree about Teluyah - Beis Shammai prohibit burning it and Beis Hillel permit it.

(B''S to B''H): Do you not say that Tahor Terumah should not be burned as perhaps a Kohen spent Shabbos within the Techum (Shabbos limits) and will come and eat it on Shabbos (which would avoid burning it unnecessarily)? The same is true for Teluyah - perhaps Eliyahu ha'Navi spent Shabbos on Har Carmel and will come and testify on Shabbos that it is in fact Tahor?!

Response (Beis Hillel): We are certain that Eliyahu will not come on Shabbos or Yom Tov.

(R. Abahu quoting R. Yochanan): R. Elazar bar R. Tzadok (of our Mishnah) follows the opinion of Rabban Gamliel. Just as Rabban Gamliel differentiates between Chulin and Terumah, that Chulin may be eaten during the 4th hour and Terumah during the 5th (as there are not many people who can eat it); so R. Elazar differentiates in their time of Biur. Therefore, just as the Halacha there follows Rabban Gamliel, so here the Halacha follows R. Elazar bar R. Tzadok.

(Mishnah): One who is going (on the 14th) to slaughter his Korban Pesach, to circumcise his son, or to eat his engagement meal at his father-in-law's house and he remembered that he has Chametz in his house; if he is able to return and destroy it and then return to the mitzvah, he should do so. If he cannot, he should annul the Chametz in his heart.

If he is going to save Jews from being chased by soldiers, to save someone from the river or from a fire or a fallen building; he should annul it in his heart.

If he is going to celebrate Pesach with friends/family, he should return immediately.

(Gemara- R. Yosa bar R. Bun): Come and see the greatness of peace (i.e. eating the engagement meal in his father-in-law's house - which causes closeness in the family/ prevents upset of the father-in-law), as it is juxtaposed with two positive commandments that are punishable with Kares - circumcising his son and slaughtering the Korban Pesach.

Question: Circumcising his son and slaughtering the Korban Pesach - which one comes first?

Answer (R. Pinchas): Since the Pasuk states (Shemos 12,48), "...he shall circumcise all of his males and then he can approach to keep it'' - this proves that circumcising his son precedes slaughtering the Korban Pesach.

(In reference to the case of the Mishnah that if going to save someone from a river etc. one does not return to destroy the Chametz) - even if he is able to return and destroy the Chametz and still go and save the person, he should not return.

(And in reference to the case of the Mishnah that if going to celebrate with friends/family he should return) - even if he is able to go and celebrate and then return and destroy the Chametz, he should not go.

Question: Surely he is going to celebrate with his Rav or someone who is greater in wisdom than him - so why does the Mishnah refer to it as a "Shevisas HaReshus'' - a voluntary celebration?

Answer: Rebbi taught in the Mishnah that action precedes study - i.e. that destroying the Chametz precedes visiting his Rav.

They decided in the attic of the house of Aris in Lod that study precedes action.

R. Abahu sent his son R. Chanina to learn Torah in Teveryah. They came and told R. Abahu that his son was involved in acts of Chesed (kindness) in Teveryah. R. Abahu sent a message to his son saying, "Are there not enough graves in Keisarin that I needed to send you to Teveryah (to do Chesed)?'' - as the Chachamim already decided in the attic of the house of Aris in Lod that study precedes action.

The Rabbis of Keisarin said that this is true when there is someone else there to act, but if not, action precedes study.

There was a story that R. Chiya, R. Yosi and R. Imi delayed in coming to study from R. Elazar in the Beis Ha'Midrash. He asked them the reason for their delay. They replied that they had been involved in an act of Chesed. He asked them if there was anyone else there to do the act. They replied that he was a convert in a foreign land without any family members to take care of him.