An Outline of the Rebbe's Explanation of Pirkei Avos
Chapter V
Likkutei Sichos Volume 15, Pages 70 - 74
פרק ה', משנה ב': עשרה דורות מאדם ועד נח. להודיע כמה ארך אפים לפניו, שכל הדורות היו מכעיסין ובאין, עד שהביא עליהם את מי המבול. עשרה דורות מנח ועד אברהם. להודיע כמה ארך אפים לפניו, שכל הדורות היו מכעיסין ובאין, עד שבא אברהם וקיבל שכר כולם.
Chapter 5, Mishnah 2: There were ten generations from Adam until Noach. This is to teach us the extent of Hashem's tolerance. All of those generations angered Him, until (ultimately), He brought upon them the waters of the Flood. There were ten generations from Noach to Avrohom. This is to teach us the extent of G-d's tolerance; for all these generations angered Him, until Abraham came and reaped the reward for them all.
The Simple Explanation
Our Mishnah teaches us several important lessons. The first generations after creation were very close to Hashem's creation of Adam. The people certainly had great insight into the power of Hashem. Nevertheless, they chose not to follow Him. The fact that G-d tolerated this behavior demonstrates His incredible mercy. Therefore, we should not wonder how the Almighty has allowed the nations to subjugate His chosen people for such a long time.
Difficulties in Understanding the Mishnah
The Mishnah speaks of two sets of ten generations each: the generations from creation until Noach, and those from Noach until Avrohom. We need to understand the different expressions used in describing these two sets of generations. Regarding the generations from Noach until Avrohom, the Mishnah tells us that Avrohom received the reward of all of the previous generations. However, regarding Noach, we find no such thing. Why is it that Noach did not receive the reward of all of the earlier generations?
The Explanation
The Zohar tells us that "Noach did not beseech G-d for mercy on behalf of the world." In other words, he did not attempt to express the merits of his generation. He did not pray on their behalf, despite knowing their fate. Contrast this with the behavior of Avrohom Avinu; he prayed fervently on behalf of the people of Sodom. He tried with all his might to save them.
In this respect, Avrohom's behavior was comparable to that of Moshe Rabbeinu. After the sin of the golden calf, he prayed valiantly on behalf of the Jews. He even carried this a step further, telling the Almighty that if you do not forgive them, "erase me now from Your book, which You have written."
We see that Avrohom helped bring about the merit of his generation. Because of the part he played in their merit, he indeed deserved to receive their reward. May we learn from our father Avrohom and our teacher Moshe how to relate to those around us. We must always give them the benefit of the doubt. We must seek their welfare, both spiritually and physically. In this way, we will all merit to be inscribed for a good, sweet year.
Adapted from the Sichah of Shabbos Parshas Re'eh, 5735