In fallen man the first power remains, the second is lost and turned into its contrary
On these premises he holds that in us, corrupted by sin, the first power remains, the material principle of acting either well or badly. The second power, the formal principle of acting well, was lost through Adam's sin.
It was not merely lost but changed into the opposite power. So all our moral faculties carry a universal resistance to the one thing that finally is acting well according to God, and it is all the more stubborn because it is ingrained from birth and reinforced by constant habit, like a second nature.
Latin
XXXIII. Quibus positis, affirmat in nobis per peccatum corruptis esse potentiam primam, sive principium materiale tam bene quam male agendi, sed amissam esse per peccatum Adami potentiam secundam, sive principium formale bene agendi, nec amissam modo, sed in contrariam potentiam conversam, ut ad id quod demum est bene agere secundum Deum, in omnibus nostris facultatibus moralibus insit universalis repugnantia, eo tenacior quod & ab ipso ortu insita est, & perpetua consuetudine, quasi altera natura, confirmata.