The following is an essay I penned for my Religions of the Western World class taken under Rutgers University conducted by Professor James Pavlin. I present this forth as my Yom Kippur present to the world. Peace!
The Jewish view of human nature is that humans were created with two inclinations: yetzer tov and yetzer hara, supported by the virtue of free-will. Yetzer tov is the inclination to act righteously and selflessly whereas yetzer hara is the inclination composed of pure and carnal primal instinct leading one to act out selfishly out of the desire for pleasure, self-gratification and survival.
In other words, using Freudian terminology, the yetzer hara is the Id and the yetzer tov is the Super Ego. Midway from the two poles stands the Law, the Ego, keeping both in check and formulating a balance between one's desire to satiate one's own passion and hunger while also tending to the needs of others.
Sin, according to the Judaic view, is any deed or action that is devoid of or goes against the Will of God, missing the mark of reconciliation with Him. However, in comparison to the Christian view of sin, it is only that and nothing more. The Will of God required for the human to submit to is outlined within the Commandments.
Sin is simply an act, not human nature or a state of being, and humans have the choice to either perform the act or abstain from it. Human nature is not inherently sinful and evil but evil and sin are inclinations of the human spirit which often overrides the the inclination to do good. It is important to note, however, that what we call an inclination for evil and sin is not the proper understanding of the yetzer hara. Even the base inclination that is considered somewhat malicious in general thought is not totally seen to be so with proper understanding.
The Gemara notes that there would be no procreation without the yetzer hara nor would a baby survive its first few years without it. The yetzer hara, and, also, the yetzer tov, are like muscles. They are both there from when we are born, but only the former is expressed, and for very good reason too, since the baby's existence and vitality depends on it not caring about the needs of others, not caring about its mother getting a full night of sleep because it itself needs to be fed, get a diaper change, etc.
As the child gets older and increasingly less needy, the yetzer tov muscle develops. With the right modeling, social experiences, and education, it learns to be patient, to share, to notice other people and how they feel, what it means to put ones own desires aside to do the right thing.
When we are older, hopefully both muscles are developed and which muscle one uses becomes a choice, the choice between right and wrong, that we make throughout our day. The Torah is an instruction book with Commandments that guide us in knowing the right choice.
That is, God has given us a set of commands to live by, for example, in the story of Genesis 3, Adam and Eve are given the command not to eat of the fruit at the center of the Garden. If human nature was inherently evil and sinful, we would see Adam and Eve eat of the fruit, that is, violate the command of God and thus perform sin immediately without temptation simply by the nature of default.
However, the story of Genesis narrates that such is not the case. Instead, Adam and Eve are tempted to sin by a snake. The snake here can be seen as the allegorical portrayal of the inclination to sin. Adam and Eve had the choice to reject the suggestion of the snake, that is, refrain from giving in to their inclination since, here, it did not serve the purpose of assuring them sustenance or survival.
Alas, they chose to do the opposite, ate of the fruit and violated the orders of God and thus sinned. This, though allowed by God to happen, was simply their own choice. So, as we can see from the story, Adam and Eve, representations of the human soul, is often tempted to sin, the temptation portrayed by the serpent, and then we, by our exercise of free-will can either choose to submit to our temptations or struggle against it and transcend against our base desires to abide by the Law of God.
— Fahim Ferdous Promi