The following study is written more convincingly than it is believed by the writer. There will be some conclusions which you come to in your Bible study of which you will never be 100% certain. I include this as an example.
The classical view of the fall supposes that as Eve's teeth sunk into the fruit, the first sin was committed, and soon afterwards Adam followed suite, resulting in the curse falling upon humanity. What I want to discuss is whether the eating of the fruit was in fact the first sin. If it was, then Eve sinned first. Straight away, the Bible-minded believer comes up with a problem: the New Testament unmistakably highlights Adam as the first sinner; by his transgression sin entered the world (Rom. 5:12). So sin was not in the world before his transgression. The ground was cursed for the sake of Adam's sin (Gen. 3:17). This all suggests that Eve wasn't the first sinner. The fact Eve was deceived into sinning doesn't mean she didn't sin (1 Tim. 2:14). She was punished for her sin; and in any case, ignorance doesn't mean that sin doesn't count as sin (consider the need for offerings of ignorance under the Law). So, Eve sinned; but Adam was the first sinner, before his sin, sin had not entered the world. We must also remember that Eve was deceived by the snake, and on account of this was " (implicated / involved) in the transgression" (1 Tim. 2:14). " The transgression" . Which transgression? Surely Adam's (Rom. 5:14); by listening to the snake she became implicated in Adam's sin. The implication is that " the transgression" was already there for her to become implicated in it by listening to the serpent. This is the very opposite to the idea of Adam being implicated in Eve's sin.
So I want to suggest that in fact the eating of the fruit was not the first sin; it was the final physical consequence of a series of sins, spiritual weakness and sinful attitudes on Adam's part. They were mainly sins of omission rather than commission, and for this reason we tend to not notice them; just as we tend to treat our own sins of omission far less seriously than our sins of commission. When we consider the Lord's teaching of Mt. 7:22,23 and 25:42-44 together, He's saying that those rejected at the day of judgment will be so on account of their omissions- hence their surprise, and anger because they knew that they had done good works; they thought that what they had committed was morally acceptable to God, and this would usher them into the Kingdom. But their sins of omission cost them the Kingdom.
What happened in Eden was that the garden was planted, Adam was placed in it, and commanded not to eat of the tree of knowledge. The animals are then brought before him for naming; then he is put into a deep sleep, and Eve is created. Then the very first command Adam and Eve jointly received was to have children, and go out into the whole earth (i.e. out of the garden of Eden) and subdue it to themselves (Gen. 1:28). The implication is that this command was given as soon as Eve was created. There he was, lying down, with his wife beside him, " a help meet" ; literally, 'an opposite one'. And they were commanded to produce seed, and then go out of the garden and subdue the earth. It would have been obvious to him from his observation of the animals that his wife was physiologically and emotionally designed for him to produce seed by. She was designed to be his 'opposite one', and there she was, lying next to him. Gen. 2:24 implies that he should have cleaved to her and become one flesh by reason of the very way in which she was created out of him. And yet he evidently did not have intercourse with her, seeing that they failed to produce children until after the fall. If he had consummated his marriage with her, presumably she would have produced children (this deals a death blow to the fantasies of Adam and Eve having an idyllic sexual relationship in Eden before the fall). Paul saw Eve at the time of her temptation as a virgin (2 Cor. 11:2,3). Instead, Adam put off obedience to the command to multiply. There seems an allusion to this in 1 Cor. 7:5, where Paul says that married couples should come together in intercourse " lest Satan (cp. the serpent) tempt you for your incontinency" . Depending how closely one reads Scripture, there may be here the suggestion that Paul saw Adam's mistake in Eden as not 'coming together' with his wife.
But Adam said something to Eve (as they lay there?). He alone had been commanded not to eat the tree of knowledge. Yet when Eve speaks to the serpent, it is evident that Adam had told her about it, but not very deeply. She speaks of " the tree that is in the midst of the garden" rather than " the tree of knowledge" . She had been told by Adam that they must not even touch it, even though this is not what God had told Adam (Gen. 2:16,17 cp. 3:2,3). So we are left with the idea that Adam turned to Eve and as it were wagged his finger at her and said 'Now you see that tree over there in the middle, don't you even touch it or else there'll be trouble, O.K.'. She didn't understand, he didn't explain that it was forbidden because it was the tree of knowledge, and so she was deceived into eating it- unlike Adam, who understood what he was doing (1 Tim. 2:14) (1). Adam's emphasis was on not committing the sin of eating the fruit; he said nothing to her about the need to multiply and subdue the earth.
The next we know, Adam and Eve have separated, she is talking to the snake, apparently indifferent to the command to subdue the animals, to be their superiors, rather than listen to them as if they actually had superior knowledge. When the snake questioned: " Yea, hath God said, Ye shall not eat of every tree..." (Gen. 3:1), Eve was in a weak position because Adam hadn't fully told her what God had said. Hence she was deceived, but Adam wasn't.
So, why didn't Adam tell her more clearly what God had said? I would suggest that he was disillusioned with the wife God gave him; he didn't have intercourse with her as he had been asked, he separated from her so that she was alone with the snake. " The woman, whom thou gavest to be with me, she gave me of the tree..." (Gen. 3:12) seems to reflect more than a hint of resentment against Eve and God's provision of her.
Not only was Adam disillusioned with Eve, but he failed to really take God's word seriously. Romans 5 describes Adam's failure in a number of parallel ways: " transgression...sin...offence...disobedience (Rom. 5:19)" . " Disobedience" translates a Greek word which is uncommon. Strong defines it as meaning 'inattention', coming from a root meaning 'to mishear'. It is the same word translated " neglect to hear" in Mt. 18:17. Adam's sin, his transgression, his offence was therefore not eating the fruit in itself; it was disobedience, neglecting to hear. That this neglecting to hear God's word seriously was at the root of his sin is perhaps reflected in God's judgment on him: " Because thou hast hearkened unto the voice of thy wife..." rather than God's voice (Gen. 3:17).
Adam's sin was therefore a neglecting to seriously hear God's word, a dissatisfaction with and effective rejection of his God-given wife, a selfish unwillingness to leave the garden of Eden and go out and subdue the earth (cp. our natural instincts), and a neglection of his duty to multiply children in God's image (cp. preaching and pastoral work). All these things were sins of omission; he may well have reasoned that he would get round to them later. All these wrong attitudes and sins of omission, apparently unnoticed and uncondemned, led to the final folly of eating the fruit: the first sin of commission. And how many of our more public sins are prefaced by a similar process? Truly Adam's sin was the epitome of all our sins. Romans 5 points an antithesis between Adam and Christ. Adam's one act of disobedience which cursed us is set off against Christ's one act of righteousness which blessed us. Yet Christ's one act was not just His death; we are saved by His life too (Rom. 5:10). Christ lived a life of many acts of righteousness and refusal to omit any part of His duty, and crowned it with one public act of righteousness in His death. The implication is that Adam committed a series of disobediences which culminated in one public act of commission: he ate the fruit.
There are three lines of argument which confirm this picture of what happened in Eden which we have presented. Firstly, Adam and Eve were ashamed at their nakedness. Perhaps this was because they realized what they should have used their sexuality for. Eating the tree of knowledge gave them knowledge of good (i.e. they realized the good they should have done in having children) and also evil (the capacities of their sexual desire?). Adam first called his wife " woman" , but after the fall he called her " Eve" because he recognized she was the mother of living ones (Gen. 3:20). By doing so he seems to be recognizing his failure of not reproducing through her as God had originally asked him. The way they immediately produce a child after the fall is surely an expression of their repentance.
Secondly, it seems that God punishes sin in a way which is appropriate to the sin. Consider how David so often asks God to take the wicked in their own snare- and how often this happens. The punishment of Adam and Eve was appropriate to the sins they committed. What Adam wasn't bothered to do, i.e. have intercourse with his woman, became the very thing which now every fallen man will sell his soul for. They ate the tree of knowledge, they knew they were naked, and then Adam knew Eve (Gen. 4:1); this chain of connection certainly suggests that sexual desire, whilst not wrong in itself, was part of the result of eating the tree. There is an artless poetic justice and appropriacy in this which seems simply Divine. What they couldn't be bothered to do became the very thing which has probably generated more sin and desire to do than anything else. Adam was to rule over Eve as a result of the fall- the very thing he wasn't bothered to do. Eve's punishment was that her desire was for her husband- perhaps suggesting that she too had no desire for Adam sexually, and therefore was willing to delay obedience to the command to multiply. They were both driven out of the garden- perhaps reflecting how they should have left the garden in obedience to God's command to go out and subdue the natural creation to themselves. Because Adam wasn't bothered to do this, even when it was within his power, therefore nature was given a special power against man which he would never be able to overcome, and which would eventually defeat him (Gen. 3:17-19). This all shows the logic of obedience; we will be made to pay the price of obedience even if we disobey- therefore it is logical to obey. Note in this context that the Hebrew behind "Desirable to gain understanding" in Gen. 3:6 "can also be translated, without notable alteration, as "desirable in order to become childless"" (2)- suggesting they didn't want to have children, they didn't want to obey the command to multiply. And therefore the curse was that they would indeed have children and suffer in doing so.
Thirdly, there seems evidence that the eating of the fruit happened very soon after their creation. Eve hadn't seen the tree before the serpent pointed it out to her (Gen. 3:6); and consider that they could eat of all the trees, but not of the tree of knowledge. But what about the tree of life? This wasn't forbidden, and yet had they eaten of it, they would have lived for ever. We are told that this tree brings forth fruit every month (Rev. 22:2); so presumably it had not fruited, implying the fall was within the first month after creation.
The practical outcome of what happened in Eden is that we are to see in Adam's sin an epitome of our essential weaknesses. And how accurate it is. His failure was principally due to sins of omission, of delaying to do God's will because it didn't take his fancy. Time and again Biblical history demonstrates that sins of silence and omission are just as fatal as sins of public, physical commission (e.g. Gen. 20:16; 38:10). To omit to hate evil is the same as to commit it (Ps. 36:4). Because David omitted to enforce the Law's requirements concerning the transport of the tabernacle, a man died. His commission of good didn't outweigh his omission here (1 Chron. 15:13). The Jews were condemned by the Lord for building the sepulchres of the prophets without erecting a placard stating that their fathers had killed them. We have a debt to preach to the world; we are their debtors, and yet this isn't how we often see it (Rom. 1:14). Israel sinned not only by worshipping idols but by thereby omitting to worship God as He required (1 Sam. 8:8). Adam stayed in the garden rather than go out to subdue the earth. Our equivalent is our spiritual selfishness, our refusal to look outside of ourselves into the world of others. Because things like disinterest in preaching or inattention to subduing our animal instincts are sins of omission rather than commission, we too tend to overlook them. We effectively neglect to hear God's word, although like Adam we may make an appearance of half-heartedly teaching it to others. And even when we do this, like Adam we tend to focus on avoidal of committing sin rather than examining ourselves for the likelihood of omission, not least in our lack of spiritual responsibility for others. Because of his spiritual laziness, Adam's sin led Eve into deception and thereby sin, and brought suffering on untold billions. His sin is the epitome of ours. So let us really realize: none of us sins or is righteous unto ourselves. There are colossal ramifications of our every sin and our every act of righteousness on others.
(2) H. Renckens, Israel's Concept of the Beginning: The Theology of Genesis 1-3 (New York: Herder & Herder, 1964) p. 270.