What was wrong with following the Halacha to take care of his own article first?

Rashi: Unless there was a clear loss involved, he should have gone beyond the letter of the law and dealt with his Rabbi's article first.

Iyun Yaakov -When a person takes care of his lost article before his father's or Rabbi's, he is following the letter of the law (rather than going beyond it). It will eventually come to pass that his son or student will take care of their lost articles before taking care of his (along the lines of Mishnah in Avos 2:6 - 'because you drowned others, they drowned you').

Maharsha: If a person actually says that he is taking care of his own before his father's, in order to fulfill the Pasuk, "so that there will not be any poor among you"; he is 'opening his mouth to the Satan' and will come to poverty.

Why was it specifically the Talmidei Chachamim in Bavel that did this?

Maharsha: It refers here to scholars before they received Semicha (as Semicha was only given in Eretz Yisrael). But in Eretz Yisrael, since Semicha could be given, one could discern who was a Chacham from whether he had Semicha. Thus, they knew exactly who to stand for.

Ben Yehoyada: In Eretz Yisrael, they did not get up fully for each other. They only partially stood up. But in Bavel, they stood up to their full height. Since they would argue in learning in a way that might have seemed to be disrespectful, they stood up fully for each other to show that they this was not the case.

Ein Eliyahu: In Eretz Yisrael, they would sit in the Beis Midrash according to their importance. Therefore, they knew who was a Chacham for whom they should stand up. But in Bavel, they would flatter each other as well as upset each other (as the Gemara states in Sanhedrin 24a) and one could not discern who was a real Chacham by observing where they sat. Therefore, since they were unsure, they all stood up for each other.

Why were they upset with each other for so long?

Maharsha: Chazal compare a person's Rav to HKB"H Himself (Sanhedrin 110a). We find that Yisrael were in a state of rejection for 40 years in the desert, because they questioned Hash-m.

R. Chananel, Maharam Shif, Ben Yehoyada: The reading should be, "'Chisda, Chisda, I do not need you; you need me for forty years'. They were upset with each other..." Rav Huna said this because Chazal teach (Avoda Zara 5b) that a student does not (fully) understand the teachings of his Rav until he has learned from him for 40 years.

How are we to understand 'Midah Ve'eino Midah'?

Tosfos HaRosh: The Midrash explains that one should not skip from Mikrah to Mishnah and from Mishnah to Talmud. Rather, one should learn in the correct order - first Mikrah, then Mishnah and then Talmud. He also should not remain learning only Mikrah, without Mishnah; or Mishnah without Talmud.

R. Chananel: If one only learns Mikrah, he has not learned the explanation of the Mitzvos.

Maharsha: The Rambam (Talmud Torah Perek 1) cites that Chazal instruct (Kidushin 30a) that one should split their time into three, between Torah, Mishnah and Talmud. He writes that this only applies when he is young. But when his wisdom has matured, he should only read the Written Torah at certain times and he should focus on Talmud. Thus:

The study of Mikrah alone is to be done only at a measured time ('Midah'), until the age of ten (when the Mishnah in Avos 5:21 instructs to begin learning Mishnah).

Mishnah is then also studied until age 15, but after that, Mikrah is studied much less. Studying both Mikrah and Mishnah in those two years between Bar Mitzvah and age 15 means that in his study of Mishnah, two-fifths of its study was done during his adult years. In contrast, since he studied Mikrah from age 5, only two-tenths of its study was done during his adult years. Thus, the study of Mikrah is only viewed as Midah Ve'eino Midah - 'good and not good'.

Why are Talmidei Chachamim seemingly viewed more stringently than Amei HaAretz?

Maharal: A Talmid Chacham lives his life using his intellect. Thus, his Shogeg (unintentional sins) are considered to be like intentional ones. Had he paid attention to what he was doing, he would not have made the mistake. It is like a person who has a candle in his hand; he is certainly able to avoid stumbling over something in the darkness if he so wishes. But an Am HaAretz is like a person walking in the darkness without a candle. If he falls, it is considered to be Shogeg. It is foolishness that brought him to sin, even if it was not Shogeg.

Pesach Einayim citing Shemen Rokeach: If a Talmid Chacham sins unintentionally, he views it as if it was intentional and repents fully for it. But an Am HaAretz views even his intentional sins as if they were unintentional. He is not remorseful and does not repent properly for them.

How are we to understand the way the Gemara expounded the Pasuk?

Tosfos: 'Your brothers... - Masters of the Written Torah' - They acknowledge that they do not know Halacha and ask those that know. 'Who hate you - Masters of Mishnah' - They think that they know as much as those who know Talmud, but they in fact do not have clarity. ''Who cast you out - These are the ignorant' - as they hate Talmidei Chachamim.

Maharsha: 'Who hate you': these are the masters of the Mishnah. The word, should not be read as 'Saneichem' - with the letter 'Sin', as 'those who hate you'. Rather. it should be read with a letter 'Shin' - 'Shaneichem', meaning those that learn Mishnah.