Nobody sins "in Adam"
.There is NO verse in all of scripture that says we sinned in Adam, you cannot possibly show it.
Romans 5:12. Therefore, just as through one man sin entered into the world, and death through sin, and so death spread to all men, because all sinned
13. for until the Law sin was in the world, but sin is not imputed when there is no law.
14. Nevertheless death reigned from Adam until Moses, even over those who had not sinned in the likeness of the offense of Adam, who is a type of Him who was to come.
Paul argues here that we all sinned in Adam, the proof being that we all die, including those who lived before the Law was given, and sin is not imputed when there is no law. Therefore, the ONLY sin for which those who sinned before the Law was given would have paid the penalty of death is
the sin that they committed in Adam. Although the Law had not yet been given when Adam sinned, he was specifically told by God,
Gen. 2:16. The LORD God commanded the man, saying, From any tree of the garden you may eat freely;
17. but from the tree of the knowledge of good and evil you shall not eat, for in the day that you eat from it you will surely die.
In the Old Testament, we read repeatedly that people are punished for the sins of their ancestors:
Exodus 20:5. You shall not worship them or serve them; for I, the LORD your God, am a jealous God, visiting the iniquity of the fathers on the children, on the third and the fourth generations of those who hate Me,
6. but showing lovingkindness to thousands, to those who love Me and keep My commandments.
Exodus 34: 6. Then the LORD passed by in front of him and proclaimed, The LORD, the LORD God, compassionate and gracious, slow to anger, and abounding in lovingkindness and truth;
7. who keeps lovingkindness for thousands, who forgives iniquity, transgression and sin; yet He will by no means leave
the guilty unpunished, visiting the iniquity of fathers on the children and on the grandchildren to the third and fourth generations.
8. Moses made haste to bow low toward the earth and worship
Deut. 5:8. You shall not make for yourself an idol,
or any likeness
of what is in heaven above or on the earth beneath or in the water under the earth.
9. You shall not worship them or serve them; for I, the LORD your God, am a jealous God, visiting the iniquity of the fathers on the children, and on the third and the fourth
generations of those who hate Me,
10. but showing lovingkindness to thousands, to those who love Me and keep My commandments.
Jer. 32:17. Ah Lord GOD! Behold, You have made the heavens and the earth by Your great power and by Your outstretched arm! Nothing is too difficult for You,
18. who shows lovingkindness to thousands, but repays the iniquity of fathers into the bosom of their children after them, O great and mighty God. The LORD of hosts is His name;
19. great in counsel and mighty in deed, whose eyes are open to all the ways of the sons of men, giving to everyone according to his ways and according to the fruit of his deeds;
Our sin in Adam was no exception.
(All quotations from Scripture are from the NASB, 1995)