Innocence of little children. The fact that we commit sin in the first place is directly attributable to Adam, and therefore unjust, since, according to Protestant theology, we didn't exist at that time and had no say whatsoever in what Adam did, and yet God created us at a later time with a sin nature precisely
because of what Adam did. (Doctrine of original sin).
In other words, we have been punished for something we had no say in and no part of, yet escape from that punishment is conditional. IE we have to become Christian.