Charles Ryrie showed the sinfulness of sinners by explaining the imputation of Adam’s sin directly to sinners and the inheritance of sin indirectly from Adam through the parents of each succeeding generation. Ryrie explained the difference:

Imputed sin is transmitted directly from Adam to each individual in every generation. Since I was in Adam, Adam’s sin was imputed to me directly, not through my parents and their parents. Imputed sin is an immediate imputation (that is, directly, not through mediators between Adam and me). This contrasts with how the inherited sin nature is transmitted. It comes to me from my parents, and theirs from their parents, and so on back to Adam. Inherited sin is a mediate transmission since it comes through all the mediators of generations between Adam and me.[1]