The word "similitude" means "likeness" of Adam's transgression. A "similitude" of God is a likeness of God but is not God. A "simlitude" of Adam's transgression is a "likeness" of Adam's transgression but is not Adam's transgression. That is precisely what our opponents believe. They believe that all men sin LIKE Adam as he is the legal precedent or likeness or pattern that God judges sin by. They deny that all mankind actually existed in one human nature in the person of Adam and actually sinned when he sinned, thus denying any likeness of his sin but actually participated in that act of sin. However, the term "similitude" refers to "even those" who died among men between Adam and Moses who did not sin in this like manner as the rest of mankind did between Adam and Moses. They did not WILLINGLY commit sin but suffered death (infants, mentally impaired). The rest who lived between Adam and Moses did sin like Adam but death is not attributed to their willful sin either as there was no REVEALED LAW that notified them that death would be the consequence EXCEPT FOR Genesis 2:17 which they could only have sinned (v. 12 Aorist tense) in the person of Adam.