1776 "Deep within his conscience man discovers a law which he has not laid upon himself but which he must obey…
Key word: “must”. 1776 is addressing “ought” not “is”. Nothing in 1776 contests the observation that people do not know what they are doing when they sin.
1777…When he listens to his conscience, the prudent man can hear God speaking…
Nothing in 1777 contesting the observation that people do not know what they are doing when they sin. Why do people not listen to their conscience? Well, people’s emotions and drives can temporarily block not only empathy, but the functioning of the conscience itself. Generally speaking it is a subconscious occurrence, not willed. When it is willed, it can be observed that the will to block out the conscience and/or empathy is done by people who do not know what they are doing.
1778 … In all he says and does, man is obliged to follow faithfully what he knows to be just and right…
key word: “obliged”. Nothing in 1778 contests the observation that people do not know what they are doing when they sin.
Here it is:
1864 “Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven.” There are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting,
rejects the forgiveness of his sins and the salvation offered by the Holy Spirit. Such hardness of heart can lead to final impenitence and eternal loss.
The way it was explained to us, again, is that God always forgives, but if a person refuses to accept such forgiveness, reconciliation cannot happen. In this very specific case, “repentance” itself is repenting from the refusal to accept forgiveness. The person is trapped. It is not that there is some limit on God’s forgiveness, but people cannot be reached that refuse to be reached. If a person is convinced that God will never forgive him and refuses to believe otherwise, he is stuck.
Augustine DOES address the person who tries to excuse them self of sin / blame etc …even from God. see ch 3 in that link
That chapter is about a person blaming God for their sins. I can’t think of how a rational person could blame God for their sins. We make the choices to behave, not God. We are not puppets.
People do “blame” God for human nature, as if it is a scourge, but it is not. Our nature is beautiful, functionally beautiful.