"The philosophy of the Christians is termed simple. But it bestows very great attention to the formation of manners, enigmatically insinuating words of more certain truth respecting God; the principal of which, so far as any earnest serious purpose in those matters is concerned, all will have received when they assume an efficient cause, very noble and very ancient, as the originator of all things that have existence. For Christians leaving to ethical students matters more toilsome and difficult, as, for instance, what is virtue, moral and intellectual; and to those who employ their time in forming hypotheses respecting morals, and the passions and affections, without marking out any element by which each virtue is to be attained, and heaping up, as it were, at random precepts less subtle—the common people, hearing these, even as we learn by experience, make great progress in modesty, and a character of piety is imprinted on their manners, quickening the moral disposition which from such usages is formed, and leading them by degrees to the desire of what is honourable and good.
But this being divided into many questions by the number of those who come after, there arise many, just as is the case with those who are devoted to dialectics, some more skilful than others, and, so to speak, more sagacious in handling nice and subtle questions; so that now they come forward as parents and originators of sects and heresies. And by these the formation of morals is hindered and rendered obscure; for those do not attain unto certain verity of discourse who wish to become the heads of the sects, and the common people is to a greater degree excited to strife and contention. And there being no rule nor law by which a solution may be obtained of the things which are called in question, but, as in other matters, this ambitious rivalry running out into excess, there is nothing to which it does not cause damage and injury" - Of the Manichees.
I have also seen it translated, less charitably, as:
"The philosophy of the Christians is fairly simple. It is mostly concerned with ethical teaching and gives only hints on the more esoteric questions of the nature of God.
...
[Christianity's] precepts are rather crude, but they do help the common people improve their lives. However, later generations subdivided this philosophy by engaging in contentious disputations to which there can really be no answer, and the people have been led into fractious quarrels too. As each of these teachers strives to impress others by the novelty of his doctrines, they have turned this formerly simple philosophy into an unspeakable mess." - Of the Manichees.
I would have put this under the Patristics, as Alexander of Lycopolis is sometimes claimed to be a Christian bishop; but this is far from certain. A lot of the work, depending how it is contextualised, may be that of a Pagan Neoplatonist.
Regardless, it clearly shows how Christianity was starting to become more sectarian, and the dangers inherent therein. This is as true in the late Third century AD as today.
But this being divided into many questions by the number of those who come after, there arise many, just as is the case with those who are devoted to dialectics, some more skilful than others, and, so to speak, more sagacious in handling nice and subtle questions; so that now they come forward as parents and originators of sects and heresies. And by these the formation of morals is hindered and rendered obscure; for those do not attain unto certain verity of discourse who wish to become the heads of the sects, and the common people is to a greater degree excited to strife and contention. And there being no rule nor law by which a solution may be obtained of the things which are called in question, but, as in other matters, this ambitious rivalry running out into excess, there is nothing to which it does not cause damage and injury" - Of the Manichees.
I have also seen it translated, less charitably, as:
"The philosophy of the Christians is fairly simple. It is mostly concerned with ethical teaching and gives only hints on the more esoteric questions of the nature of God.
...
[Christianity's] precepts are rather crude, but they do help the common people improve their lives. However, later generations subdivided this philosophy by engaging in contentious disputations to which there can really be no answer, and the people have been led into fractious quarrels too. As each of these teachers strives to impress others by the novelty of his doctrines, they have turned this formerly simple philosophy into an unspeakable mess." - Of the Manichees.
I would have put this under the Patristics, as Alexander of Lycopolis is sometimes claimed to be a Christian bishop; but this is far from certain. A lot of the work, depending how it is contextualised, may be that of a Pagan Neoplatonist.
Regardless, it clearly shows how Christianity was starting to become more sectarian, and the dangers inherent therein. This is as true in the late Third century AD as today.