Original sin in the Hebrew Bible

4:123"(This) shall not be in accordance with your vain desires nor in accordance with the vain desires of the followers of the Book; whoever does evil, he shall be requited with it, and besides Allah he will find for himself neither a guardian nor a helper"

 

Many verses of the HB are used to defend this doctrine, including 

Ps51"I was shapen with iniquity; and in sin did my mother conceive me". 

David states he was created with/in sin (the letter used to indicate ‘in’ can also mean ‘with’) and cites the reason; he is the product of sin, and this implies that parents pass onto the children's genes not only a physical but also a spiritual baggage. This creates an inclination towards sin, not that the person is an accountable sinner simply due to that defect, in accordance with verses like Deut24:16 clearly stating that none is punished for the sins of the ancestors. That inclination to sin, not the state of being a sinner, can be overcome using freewill as seen in Cain's story. David in that passage recognizes his inclination to sin due to his innate spiritual defects, expresses his sorrow for his sin with Batsheba, and pleads for mercy on account of that sinful impulse. 

In line with the story of Cain who was told by God to make the right choice by himself, because it was within his reach, the same David similarily recognizes that uprightness of heart is a condition that can be achieved by the righteous, who can thereafter keep himself from sin 

Ps18:22-23"All his laws are before me; I have not turned away from his decrees. I have been blameless before him and have kept myself from sin" Ps32:11"Be happy in God, and rejoice O righteous. Cry out in joy, all upright of heart" 

and by the one who freely 

Ps34:14"Turn from evil and do good; seek peace and pursue it". 

This does not agree with the Christian notion of inherited sinfulness that can never be overcome by humans alone and their own freechoices and deeds, hence the necessity of a global sin offering incarnated by Jesus. In fact the NT even speaks of John's parents being upright in God's sight for their righteousness and blameless observance of the Law Lk1:6.

Another verse used is 

Gen8:21"I will not continue to curse again the ground on account of man, since the inclination of the heart of man is evil from his youth". 

It doesnt say "at birth" as implied by the proponents of the sinful nature doctrine, it says "youth" because children are predominantly selfish until they mature. Maturity coincides with the development of the good inclination, at which point Man is considered responsible and possessing free will. 

Job11:12 says, "man is born a wild mule" but adults can do better. Sometimes Prov20:9 is quoted, in disregards of 

20:7"He who walks in innocence is righteous, fortunate are his sons after him". 

Prov20:7-9 speak of how an honest person can find a misdeed in his past. However, innocence and righteousness are not fictional.

Jer5:1 is cited to prove no righteous person exists for no righteous was found in Jerusalem's public places yet Ps79:2 when describing Jerusalem's siege says there were righteous people in Jerusalem at that time, only they were not found in public places.

Jer13:23 is clearly an exaggeration by the prophet, meaning that change requires serious effort. In fact in every chapter, Jeremiah tells the people to correct their behavior on their own without preconditions so to argue he meant that none could do it, would be an absurdity. Another verse is 

Jer17:9"The heart is deceitful above all things and beyond cure" 

other translations say 

"The heart of man is desperately wicked who can know it". 

So if man's heart is doomed to wickedness, how will Jesus' sacrifice solve the problem? There is no exceptional clause anywhere in or near the verse. This also is a case of exageration, for Jeremiah clearly calls his addressees to mend their ways and in fact the next verse states that God looks in each person's heart "to reward each person according to their conduct, according to what their deeds deserve". There is good just as there is an evil tendancy and man must, on his own, choose the former, or in God's words to Cain concerning his sinful self 

Gen4:7"you must rule over it".

While Adam is created by God in His image, Adam begets Seth in Adam's image Gen5:1-2 after having being stained by the sin. Supposedly, the Divine image was negated yet Gen6:5 says (after the Flood) that the image of God is the reason for the prohibition of murder.

Often used is also 

Ecc7:20"There is no righteous man on earth who does what is right and never sins"

 to prove that unless one attains absolute perfection (which he cannot), all is lost. Yet when one looks closer at the verse, it actually says 

"There is no RIGHTEOUS person..who never sins". 

The person who does a sin is still righteous.

There are different types of sin in the Torah:

Pesha - An intentional sin, committed in deliberate defiance of God
Ovon - A sin of lust or uncontrollable emotion, done knowingly but not done to defy God;
Cheit - An unintentional sin, the word comes from an arrow that misses its target. The result may have ramifications, but the act was not done with malice aforethought.

Most of the time they are defined through context (an act of rebellion against God or pesha is not the same as an unintentional sin or chait)

The sin commited by Adam and Eve was cheit, because it was neither a pesha nor an ovon. God then gave them the opportunity to repent: he asked Adam "Where are you?" God knows all things so his intention was to give Adam an opportunity to admit what he had done wrong, which they didnt: Eve blamed the serpent (not a regular snake, but a snake like creature whom Torah says was very intelligent, that could communicate (like other beasts are made to speak in the HB) and that implicitly could have stood erect prior to being inflicted with the divine curse. It is worthwhile noting, snakes have muscles that could be used for walking, they even have the right genes to develop limbs. In pythons the gene is sometimes triggered causing small claws to protrude from their skin: They are beginning to develop limbs) and Adam blamed Eve. 

God doesnt punish anyone immediately after eating from the tree, because it was a cheit type of "sin" or mistake as seen from its use in Judges20:16. It is after the immature finger pointing and refusal to take responsibility and repent that God sends everyone out of the garden meaning what really caused their banishement was their stubborness and refusal to repent, otherwise they would have been sent away right after eating from the tree. Therefore the real sin was not eating the forbidden fruit (cheit, mistake) rather it was the fact of not taking responsibility and refusal to repent. 

Then God curses the serpent with "arur atah" which is never used next when He addresses Adam and Eve. God tells them "arurah ha'adamah", cursed is the earth/ground. This speaks of the earth/ground that Adam will have to work - but God does not curse Adam nor Eve. 

This is the major point lost by Christians, God did not curse (arur) Adam nor Eve by causing them to unwillingly inherit a sinful nature to their descendants; they were punished (not cursed = arur) with the pain from childbirth, subjugation of women to men, and having to work for food. 

This has nothing to do with sin or cursing man with a sinful nature. 

As to Gen3:15, the seed of Eve spoken of, refers to mankind in general because God here is addressing Eve. 

Similarily in Gen16:7 Hagar's seed refers to her Ishmaelite descendants because she is being addressed, not Abraham. The passage of Gen3 isnt figurative and its plain reading is obvious, refering to the enmity between serpents and humans. Some Christians like to see in that passage an allegory of Jesus' utter defeat of Satan, which obviously didnt happen. Satan is still active even among those that are most adamant in their belief in him, such as Paul 1Thess2:18. Paul also made the false prophecy that this anticipated defeat shall happen very shortly Rom16:20. 2000 years later, sin still exists, even among those that accepted Jesus, just as it remains a threat to those that sincerely repent 1Jn1:8,3:8-9.

Whether man is a sinner by nature or not is immaterial to Judaism since it teaches the way to repentance and reconciliation with God.
The Torah says man has an inclination towards evil from youth not birth Gen8:21 but that doesnt make everyone a sinner from birth, having inherited Adam's sin, nor does it mean one is in a state of being from which he must be "saved". In fact even the non Jewish king of Tyre was found to be 

Ezek28:15"perfect in your ways from the day you were created until wrongdoing was found in you". 

Each person is accountable for his own sins and can find the way to forgiveness through sincere repentance and resolve in walking aright Ezek18:20-22,Deut24:16,2Kings14:6,Jer31:30,Job34:23. The passages often used in support of the transmissibility of sins, from father to son for example as in the context of the punishement of the Israelite nation throughout Jeremiah and Ezekiel, disregard the statements in those same books, saying that the son who does not walk in the footsteps of the sinful father is never punished for the latter's sins, only those who follow the sins of the parents are punished Ezek18:17-19.

Moral responsibility only applies after reaching maturity Deut1:39,James4:17. Man chooses to sin Isa66:3-4, against his good nature Eccl7:29, just as he can 

Ps34:14"Turn from evil and do good; seek peace and pursue it". 

This is illustrated through the story of Abel and Cain. 

In 

Gen4:7"Is it not so that if you improve, it will be forgiven you? If you do not improve, however, at the entrance, sin is lying, and to you is its longing, but you can rule over it" 

God speaks to Cain and tells him that good and evil are his choices and that he should choose good. God tells Cain that he can master evil and avoid falling in sin, it is an advise to choose the right path or face the consequences of sin. There are therefore 2 possibilities depending on Cain's choice.

If God tells him that he must master evil it means it is in his capability, that there is no sinful nature unwillingly imposed on him preventing him from doing any type of good and following a command from God, otherwise why would He tell him to master his evil thoughts, why would God tell him to do something impossible to him and punish him for failing. 

Later, Cain chooses to sin by killing his brother. This was done out of his freewill, and his failure to master his evil tendency does not mean that he didnt have the ability to do any good. If it was the case, God would not have told him that good and evil were his own choices, nor order him to master evil or face the consequence of his sin. 

The most prevalent theme in the Jewish scriptures is that God relates to people according to their deeds, both good and bad. The sinful nature of man does not cancel out any good that we do, the actions of men find favor in the eyes of God Gen26:4. David is pointed as an example of righteousness that others should follow 1Kings11:38. This does not mean that he was sinless - he wasn’t. But it does mean that his sins did not nullify the good that he did.

 God chose to save life on this planet through the handiwork of the righteous Noah. Noah’s ark, which was built by Noah’s obedient action, was the means through which God recreated the world. The message is clear 

Prov10:25"And the righteous one is the foundation of the world".

Just like in Islam, freewill is a foundation of Judaism. From the very beginning, mankind's original design already included the capability of free will. The textual proof of this in the HB is that God issued a commandment to Adam; God doesnt issue pointless commandments and - if mankind lacked the free will to obey or disobey - then every commandment would be pointless. 

Deut30:19"I call heaven and earth to bear witness this day, for I have set before you life and death, the blessing and the curse. Therefore, choose life, so that you and our children may live"

Lamentations3:38"Evil and good come not from the mouth of the Most High. Why then should a living man complain, a strong man, because of his sins?"

 this explains that if a person chooses evil and fails to heed the call to righteousness, he has no cause to complain, for the decision is his alone.

Ps24 explains that man is given a pure heart also Gen8:21 says that mankind has an "evil inclination" (evil in their heart, which is not a sin) from their youth, not from birth. This verse also lifts the curse put on the earth by God meaning the only curse left was the one on the serpent, Adam and even were never cursed. 

The Hebrew Bible explains that sin comes as a result of not following God's commandements, one cannot be born "sinful". It isnt a hereditary disease that is transferred from a father to his son. There is not one single prophet or prominent personality in the Hebrew Bible (who dwell at length upon the iniquities of the Israelites) who saw in the story of the Tree of Knowledge any special “sin” that is worth mentioning.

When God tells Adam if he eats from the tree "you will surely die" it has nothing to do with eternal damnation to him and his progeny, if Adam obeyed God, he could remain in the Garden, enjoying a close relationship with God. However, should he disobey, he is to die. In the next chapter, the penalties of this 'death sentence' are announced and they are the banishement from the garden and a life of toil and sorrows. In biblical terms, becoming distanced from God is tantamount to death (deut30:15-20). Its a spiritual death or "cut off".

If taken literally it still doesnt hint to any eternal damnation: "you will surely die" (mot tamut) describes a process of death. "mot" is the state of death while tamut = ata-mut is how you (ata') will get there, it indicates the beginning of dying, an ingressive sense. In other words, if they would have eaten the fruit, then Adam and Eve would have begun to die and would return to dust as indicated in context in 

Gen3:17 "all the days of your life”,

 and 

"by the sweat of your brow you will eat bread. Finally (or until) you will return to the ground, for it was from (the ground) that you were taken. You are dust, and to dust you shall return "

 it is a process of death which begins from birth. A more proper translation would be 

"unto death you will die”.

The rabbis teach that before eating from the tree it was easy to tell the difference between good and evil, like black and white. 

If Adam and Eve had waited, God would have given them permission to eat of the tree (when they were mature enough to understand it,after Shabbat). But by choosing they gained the knowledge before they had the wisdom to control it, resulting in a difficult distinction of good and evil, which is why man is more inclined towards evil but can MASTER it. It is also interesting that while the serpent was cursed Adam and eve were not cursed.

The fact is that trinity needs the illogical and immoral original sin to open the way to Jesus, who was part of a great plan from the heavenly father to redeem mankind from the stain burdened on all because of Adam and Eve's desobedience.