To Florus 3.189
Observe the conclusion: denying grace does not attach to praising human nature. Rather, these four positions are so connected that one cannot be maintained without the other: defaming nature produces denial of grace, and praising grace produces commendation of nature. These implications can run in either direction. You therefore spoke well: ‘If human nature were evil, it ought not to be saved’ (Augustine, Marriage and Sexual Desire 2.36). The Manichaeans say both things: flesh’s nature is evil, and it neither can nor ought to be saved through grace.
Latin
Quid igitur hinc conficiatur, adverte; non adhaerere negationem gratiae laudi humanae naturae, quin immo haec quattuor ita esse coniuncta, ut alterum sine altero teneri nequeat, sed infamia naturae pariat negationem gratiae et laus gratiae pariat praedicationem naturae; ista enim in quamvis sibi partem reciprocari possunt. Bene ergo dixisti: Natura humana, si malum esset, salvanda non esset [n246] ; hoc enim dicunt utrumque Manichaei, malam videlicet carnis naturam nec posse salvari per gratiam nec debere.