S. Augustine, on the Nature of the Soul and the Lunacy of Manichaeans

Nec sane multum mirandum est, quod hi qui nonnullam malam putant esse naturam suo quodam contrario exortam propagatamque principio, nolunt accipere istam causam creationis rerum, ut bonus Deus conderet bona; credentes eum potius ad haec mundana molimina rebellantis adversum se mali repellendi extrema necessitate perductum, suamque naturam bonam malo coercendo superandoque miscuisse, quam turpissime pollutam et crudelissime captivatam et oppressam labore magno vix mundet ac liberet, non totam tamen; sed quod ejus non potuerit ab illa inquinatione purgari, tegmen ac vinculum futurum hostis victi et inclusi. Sic autem Manichaei non desiperent vel potius insanirent, si Dei naturam, sicuti est, incommutabilem atque omnino incorruptibilem crederent, cui nocere nulla res possit: animam vero quae voluntate mutari in deterius et peccato corrumpi potuit, atque ita incommutabilis veritatis luce privari, non Dei partem, nec ejus naturae quae Dei est , sed ab illo conditam longe imparem Conditori christiana sanitate sentirent.*

It is not, however, very surprising that people, who think that some evil nature has been produced and propagated by its own opposing principle, refuse to admit that the true cause of creation is that the good God created good things.  They prefer to believe that He was forced into the great task of world-building by the urgent necessity of driving back the evil that rebelled against Him, and that with the idea of restraining and conquering that evil He mixed His good nature with it, which now, shamefully polluted and cruelly imprisoned and enchained, He now for all His labour can scarcely cleanse and deliver.  Indeed, He does not seek to clean it all: that part of it which cannot be purified from defilement is to serve as a chain for the conquered enemy and to be the prison of his confinement.  The Manichaeans would not drivel, or rather, rave in this fashion, if they believed the nature of God to be, as it is, unchangeable and altogether incorruptible, so that nothing can injure it.  Nor, again, would they do so, if with proper Christian orthodoxy they held that the soul, which by its own will can be changed for the worse and corrupted by sin and so deprived of the light of immutable truth, is not a part of God, nor of the same nature as God, but was created by Him, and is very different from its Creator.**

*The text is taken from Migne’s Patrologia Latina
**Trans. F. A. Wright Fathers of the Church (1929)