When God created the first man and woman, they were created with the ability to keep God’s law and because they were free, they were also able to not keep God’s law. Adam was our representative, meaning that he represented all who came after him and when he sinned he took all future humans with him into sin in the same way an anchor takes its chain (not fastened to the ship)  in to the sea when dropped. This is hard to understand by many today who think they live independent lives. Whatever people believe, the evidence of our fall into sin with Adam is found in our thoughts, words and actions.