Halakhah do Terumot 11:11

And this is the language of the Tur: The Ittur writes that were I not afraid of other rabbis I would say that even a earthenware pot that has not been used for 24 hours since it is only a rabbinic prohibition to cook with it, can be kashered through immersion in boiling water three times and this is sufficient. And the Ittur brings proof from the Yerushalmi (Terumot 11:4). And the Rashba writes teh same thing and concludes his words by saying that perhaps this is only permissible with a rabbinic prohibition that has no basis in a Torah prohibition like Terumah or Challah outside of Israel in our times or with bishul akum (food cooked by Gentiles) but for other rabbinic prohibitions that do have a Torah basis they were strict just as with Torah prohibitions and it is appropriate to be concerns and not be lenient. All of the above is the language of the Tur. And so this leniency is entirely unmentioned in the Shulhan Arukh except for a reference in Siman 113 regarding bisul akum (food cooked by Gentiles) see there. And the Rashba in Torah haBayit discusses this at great threngh and writes that whenit comes to the strict law it appears to him that all rabbinic prohibitions should be permissible under these circumstances as the RaSh HaTzarfati writes and see there. And the Tur didn't bring the end of the Rashba's words because he was of the opinion that one should not be lenient in this way in a practical fashion. And, heaven forfend we should not violate the opinion of the Tur and Shulhan Arukh, however this is very puzzling since the Yerushalmi in Pesachim (3:1) says that when it comes to Hametz, which certainly has a foundation in Torah and the Yerushalmi there says: Rabbi Yirmiyah saidi n the name of Rav, a pot in which hametz was cooked should not be used for the same type of food until after Pesach, but a different food can be cooked in that pot even on Pesach if three items were cooked in between. And the commentator has already raised this question.

From the laws of the commandment - that which they, may their memory be blessed, said (Beitzah 13a) that a [Levite] who took sheaves as tithes, does not give sheaves to the priest from it, but he is fined to pound and winnow [it] and to give him a tithe of the tithe that is a tithe of grain, and he is not obligated to give a tithe of the straw [byproduct], after he pounded everything and winnowed [it], but if he first tithed the sheaths, and [then] pounded and winnowed [it], he must give [the priest] his portion in everything; that which they said (Mishnah Terumot 11:8) that only priestly tithes from the tithe with [at least] 1/64 of a log must he take to the priest, and so long as the priestly tithe is certain (not in doubt) and pure, [but] if it is less than this, he need not busy himself with taking it to the priest, but he rather throws it into the fire and burns it; that which they said (Mishnah Bikkurim 2:5) that the priestly tithe from the tithe can be separated from that which is not [close], as it is stated (Numbers 18:28-29), "From all the tithes [...] you shall gift," meaning to say even if you have a tithe in one country and [another] in another country, you may take one gift for all [of them], but nonetheless they, may their memory be blessed, said (Gittin 30a) that Torah scholars should only take it from [what is close]; and the rest of its details - are elucidated in Tractate Terumot, Ma'asrot, and in parts of Demai (see Mishneh Torah, Laws of Heave Offerings 1).