We mention the Exodus from Egypt at night. R’ Elazar ben Azaryah said: Behold, I am like a seventy-year-old man, yet I did not prevail [with my argument] that the Exodus from Egypt should be mentioned at night, until this was expounded by Ben Zoma: For it is stated: So that you will remember the day of your departure from the land of Egypt all the days of your life (Deuteronomy 16:3.). The days of your life — [this means] the days; all the days of your life — [this includes] the nights [also]. But the Sages say: The days of your life — [this means] this world; all the days of your life — [this comes] to include the days of the Messiah.

R' Chanina, administrator of the Kohanim, says: In all the days of the Kohanim, never did they refrain from burning [sacrificial] meat that had been contaminated by a secondary tumah together with [sacrificial] meat that had been contaminated by a primary tumah, although [by so doing] they added contamination to its contamination.  R' Akiva added, saying: In all the days of the Kohanim, never did they refrain from lighting oil that had become unfit [through contact] with a t'vul yom in a lamp that had been contaminated by one contaminated by a corpse, although [by so doing] they added contamination to its contamination.