It says in Beresheis 6:11-13; “And the Earth became corrupted before Hashem, and the Earth was filled with robbery. And Hashem saw the Earth, and behold, it was corrupted, for every living creature had corrupted its way upon the Earth. And Hashem said to Noach, ‘The end of all living creatures has come before Me, for the Earth is filled with robbery through them, and behold, I will destroy them from the Earth.’”
It says in Pirkei Avos 4:11 that our Chochamim tell us that when every person does an Aveira he creates an antagonist for himself in a form of a Malach of Destruction but it cannot harm this person until the sentence is passed in the Heavenly Beis Din. The Ohr Hachaim explains that this is forbearance which is preventing this Malach in harming the person prior to judgment. Once the person is judged and found guilty, the Malach that which you created through your Aveira is now free to wreck its devastation, so the person is in fact the author of his very own punishment.
There is a general rule, however, that when the sins of a person are so numerous as well as serious that the person’s guilt is a forgone conclusion, in that case the Malachim of Destruction are granted permission even before the sentence has passed. This was the fate of the Generation of the Great Flood, for their Aveiros were so numerous and serious that the Malachim of Destruction were unleashed before the generation was tried by the Heavenly Tribunal.
Rashi says their fate was sealed because of robbery. Why was robbery the one that sealed the Generation of the Great Flood more than any other Aveira that they committed?
The Zera Shimshon answers that because of thievery everyone was steeped in immorality as well. It says in Yalkut Shimoni Iyov: 909 that the people walked around without clothes on because thievery was so rampant that people were afraid to wear clothing for they feared someone would steal it off their backs. It would have been bad enough in the eyes of Hashem if people walked around immodestly because of an innate lack of tzniyus, but walking around without clothes because of a thievery issue was worse.
Another reason that thievery was the Aveira that caused that Generation total annihilation is because regardless of how serious the Aveiros that the entire generation committed, Hashem was prepared to deal mercifully with the people. However, since the people showed no mercy to other people when they robbed someone without the least compunction, they lost the benefit of all merciful treatment. It was because of this lack of mercy and care toward one another that sealed their fate.
What we must take from here is that now we that have begun the month of Mar Cheshvan we must continue to grow in the way that we were during all the Yomim Tovim of last month. All Klal Yisroel should continue to grow in Torah and Chesed and know that the total opposite of thievery is doing Chesed for one another. It’s also another way we can bring about Achdus among Klal Yisroel. If all Klal Yisroel acted on this, we can do the opposite of the Generation of the Flood and when Hashem sees us acting with Chesed with one another as well as unitying, Hashem will bring the Final Geulah.