Adam is both the name of the first man and a Hebrew word that means "human." Paul emphasizes Adam's connection with the human race.
sin entered the world: The importance Paul gives to this act, and the way he compares Adam’s sin with Christ’s obedience on the cross, shows that Paul understood Adam and the sin in the garden of Eden as real events in history.
all sinned: Death affects everyone because sin affects everyone. It is uncertain when or how all sinned. But Paul later attributes the condemnation of all people to the sin of Adam, their representative (5:18).
Jewish tradition is not united on how Adam’s sin relates to the sin and death of all human beings. Different Jewish texts explain this relationship in different ways.
Some texts teach a strong connection between Adam and all other people. These writings say that Adam’s sin brought death to the whole human family. One example says, “when Adam sinned, a death was decreed for those yet to be born” (2 Baruch 23:4). Other texts place responsibility on each individual person. These writings say that people die because of their own sin, not because of Adam’s sin. One text states, “Adam is not the cause, except for himself; each of us has become our own Adam” (2 Baruch 54:19).