We know from both mishnayos and from the piyutim that we recite on Rosh Hashanah and Yom Kippur that this period of the year is when Hashem judges the world. After the Ramban succeeded in a debate with a Jewish meshumad he realized that he better leave Spain because his life would definitely be in danger. He ran away to Eretz Yisroel and gave a very long drasha that Rosh Hashanah covering all of the topics of the yom tov. A major issue that he brings up in that drasha is that this idea that the Aseres Yemei Teshuva are the days of judgment never appears anywhere in Tanach, so how did Chazal know this is the case?
Rambam quotes midrashim which say that Adam Ha'rishon was created on the sixth day of Bereishis, instructed not to eat from the eitz ha'daas, violated the instruction, and was judged and punished, all on the same day, and was chased out of Gan Eden. At that time, Hashem told Adam Ha'rishon that just like He judged him on that day, so too, in all the future generations, all of his descendants will be judged on that day, Rosh Hashanah. The Ramban therefore suggests that Aseres Yemei Teshuva being the days of judgment was not a tradition that Moshe Rabbeinu received at Har Sinai, rather a tradition from Adam Ha'rishon.
The Torah tells us that Adam was created b'tzelem Elokim. The Meshech Chochma explains that having a tzelem Elokim implies that each of us has bechira chofshis. Many psychologists do not believe in bechira chofshis, but it is considered one of the most important principles of the Jewish religion.
Every morning we say to Hashem in our tefillos that the neshema that You implanted in my body was given to me in a pure state. We do not believe that because of the "original sin" all human being's souls are all tainted. We are born with a pure soul and if and when we sin, then we taint it. The commentaries on Chumash wonder what the significance was of recording of the story of the eitz ha'daas in the Torah if it is not relevant to us. They explain that the Torah recorded this incident to teach us how a typical human being might fall into the trap of sinning.
The Ramban in his commentary on the first perek in Chulin quotes a very fascinating medrash. The prohibition against eating from the eitz ha'daas was only a horo'as sha'ah. Adom Harishon was told that Friday morning that if he will wait until leil Shabbos he will be permitted he will be able to eat those fruits; it was only for the duration of the few hours of erev Shabbos that it was prohibited to him. The medrash comments that we ought to dig up Adam Harishon from his grave, remove the sand from on his eyes, and show him how the Jewish people always exercise self-control. If a married woman has not gone to mikvah, the husband knows that he has to wait a week or two. When we shecht an animal, we do not eat from the meat right away, rather we wait until we check the lungs to see if it is treif. When we plant a tree, we know that the first three years we may not eat any of the fruit because of the mitzvah of orlah. The Jewish people have learned the lesson of self-control.
The Chumash describes the aseres ha'dibros as being chaurs - engraved - on the luchos. The mishna in Pirkei Avos comment that the posuk is implying that real cheirus (freedom) can only be found by those who learn Torah and live a life of Torah. Many people have caused themselves to lose part of their bechira chofshis. They are enslaved by their yetzer harah (desires) and have not at all trained themselves in self-control. By giving the Torah to the Jewish people, Hashem gave us the ability to free ourselves from this enslavement and be true benei chorin who exercise their bechira chofshis. The posuk in Koheles praises that country whose king is a "Ben Chorin" and woe unto the country whose king is a slave. The Zohar understands that the posuk is praising Eretz Yisroel whose official king is Hashem who is the one who gives freedom to human beings. He is the one who enables human beings to train themselves in self-control and to not be enslaved by their yetzer harah, and thereby be able to exercise their bechira chofshis in a more complete fashion.
During this season of the year, Hashem makes himself more readily accessible than all year long. The navi Yeshaya encourages us to search out Hashem specifically during the Aseres Yemei Teshuva. May we all seize that opportunity before the yom ha'kodosh to come closer to Hashem Who created the entire universe yeish m'ayin, and by coming closer to Him we will strengthen our bechirah chofshis to make reasonable and balanced decisions in life by exercising our self-control.
We should all have a g'mar chasima tovah.