Yet without internal grace, right use of faculties is morally impossible
Still: mind and will are sin-corrupted.
Without inward grace lighting the mind and bending the will, right use cannot happen.
Obeying the outward call needs that inward help.
Without it, obedience is morally impossible because of inherent vice.
Latin
XX. Agnoscunt autem istas naturales hominis facultates, nempe mentem atque voluntatem, ita peccato corruptas & vitiatas esse, ut nisi accedat interna quaedam Dei gratia, quae mentem illuminet & voluntatem flectat, contingere non possit ut homo bene utatur suis illis facultatibus, & pareat atque obsequatur Deo vocanti & invitanti ad gratiae suae extrinsecus oblatae participationem; quod illi propter vitium inhaerens, absque interna ejusmodi gratia moraliter impossibile est.