Our last post considered the suggestion that human beings either gained something (a “sinful nature”) or lost something (leading to the inability to obey God) at the moment Adam sinned. In this post we will briefly consider the “doctrine of inability.”
When considering the moral obligation of human beings, the doctrine of inability is redundant. It is redundant because God only and always expects us to use whatever amount of ability we possess. Consequently, if we possess no moral ability to obey God, He expects no moral obedience as this, otherwise, would be to demand the impossible. Moral inability eliminates moral agency, which eliminates moral obligation, which eliminates moral concepts such as sin and righteousness.
Scripture reveals that even after the sin of Adam and Eve, God expected moral obedience and held people morally accountable.
When addressing Cain, God said, “If you do well, will not your countenance be lifted up? And if you do not do well, sin is crouching at the door; and its desire is for you, but you must master it” (Ge.4:7). The simple conclusion from this statement is that God believed that it was possible for Cain to “do well” and that he possessed the ability to “master it” (sin).
I close this post with the following quote: “…this commandment which I command you today is not too difficult for you, nor is it out of reach. It is not in heaven, that you should say, ‘Who will go up to heaven for us to get it for us and make us hear it, that we may observe it?’ Nor is it beyond the sea, that you should say, ‘Who will cross the sea for us to get it for us and make us hear it, that we may observe it?’ But the word is very near you, in your mouth and in your heart, that you may observe it” (Dt.30:11-14).
 This is true of any loving and reasonable being. Would we consider a father to be loving and reasonable if he expected his children to do that which they had no ability to do, threatening severe punishment if they failed? Consider a child with a crippling disability preventing them from being able to walk. Would a loving and reasonable father demand that they walk and punish them if they do not?