Against the Epistle of Manichæus, Called Fundamental 2
2 Why the Manichæans Should Be More Gently Dealt with PL 42, 174
2. Let those rage against you who know not with what labor the truth is to be found and with what difficulty error is to be avoided. Let those rage against you who know not how rare and hard it is to overcome the fancies of the flesh by the serenity of a pious disposition. Let those rage against you who know not the difficulty of curing the eye of the inner man that he may gaze upon his Sun,—not that sun which you worship, and which shines with the brilliance of a heavenly body in the eyes of carnal men and of beasts,—but that of which it is written through the prophet, "The Sun of righteousness has arisen upon me;" and of which it is said in the gospel, "That was the true Light, which lighteth every man that cometh into the world." Let those rage against you who know not with what sighs and groans the least particle of the knowledge of God is obtained. And, last of all, let those rage against you who have never been led astray in the same way that they see that you are.
Causae cur mitius agendum cum Manichaeis. Illi in vos saeviant, qui nesciunt cum quo labore verum inveniatur, et quam difficile caveantur errores. Illi in vos saeviant, qui nesciunt quam rarum et arduum sit carnalia phantasmata piae mentis serenitate superare. Illi in vos saeviant, qui nesciunt cum quanta difficultate sanctur oculus interioris hominis, ut possit intueri solem suum: non istum quem vos colitis coelesti corpore, oculis carneis et hominum et pecorum fulgentem atque radiantem, sed illum de quo scriptum est per prophetam, Ortus est mihi justitiae sol ; et de quo dictum est in Evangelio, Erat lumen verum, quod illuminat omnem hominem venientem in hunc mundum . Illi in vos saeviant, qui nesciunt quibus suspiriis et gemitibus fiat, ut ex quantulacumque parte possit intelligi Deus. Postremo, illi in vos saeviant, qui nunquam tali errore decepti sunt, quali vos deceptos vident.