After Rav Sheshet’s first failed attempt to prove that an uncircumcised man cannot partake in maaser sheni, the second tithe, the Gemara tries to bring three other sources to prove this as well. But all attempts are rejected – the first two because they can be explained as referring to maaser rishon, the first tithe and the last one as it can be attributed to Rabbi Akiva. Rabbi Yitzchak held as Rav Sheshet and proves it from a gezeira shava from Pesach, using the word mimenu. That gezeira shava can be difficult as Pesach is more stringent and therefore they must prove that one (or two, depending on how one holds on this issue) or the mentions of the word are unnecessary and therefore can be used for the gezeira shava. There are 3 mentions of the word mimeni in maazer sheni and in Pesach – what are they all needed for and which is unnecessary? Now that the Gemara finished dealing with the first word in the Mishna (that an uncircumcised man can’t eat truma), they move on to the next case – an impure person. From where is this derived? The verse in Vayikra 22:4 discusses an impure kohen who can’t eat sanctified items – the Gemara proves that it is referring to truma. The verse there says after they are purified, they can eat it – how do we know that it means until the sun sets and not until one brings a sacrifice, in the event that one is obligated to bring a sacrifice, as it the cases in the verse (zav and leper)? Rabbi Yishmael explains that it is a zav or leper that do not need a sacrifice (zav – saw only two discharged, leper that was not a definite leper, musgar – only quarantined). They further explain that in case one may have thought that in a case where there is a sacrifice, perhaps one would need to wait until the sacrifice is brought to be able to eat truma, the Gemara brings the sources in the Torah for the law stated in a Mishna Negaim 14:3) that differentiates between eating maaser - immediately after immersing in a mikveh – truma - after sunset - and sacrificial items – after the sacrifice is brought. From which verses are they derived and why is it clear that each one is referring to that specific issue (maaser, truma or kodesh) and not to a different one?