Resh Lakish's explication of the text, in providing the source for ma'aser sheni becoming impure and then available for use to anoint one's body. Which aligns with what is done for the living and the dead in the same way. Plus, the various interpretations of the biblical term that accounts for the above as well. Also, another derivation from a verse - about impure kohanim who must purify before they can eat terumah. Likewise, who has to bring korbanot as "bar kapparah," those who need atonement (zav and metzora) - when is their time of purification? A range of times are able to be derived from the verse. And, another mnemonic... for where terumah is treated more stringently than ma'aser sheni. Plus, some thoughts on why these topics are getting so much attention.