The Fall of Adam has done more than simply leave us prone to sin. There is conflict within all of us.
“Man is divided in himself. As a result, the whole life of men, both individual and social, shows itself to be a struggle, and a dramatic one, between good and evil, between light and darkness” (§1708).
We all have problems whether we see them or not, whether we believe it or not. So we ought to be patient with each other and with ourselves.