I'm sure that Plotinus wasn't that impressed by the Christians.

Assuming there is an intellect, we're clearly not this universal intellect or we would know it. So that's one function of soul.

The forms in intellect are some kind of blueprint or model on which the physical world is based, and something needs to come along and shape the matter in accordance with that blueprint. What does that is soul.

Unlike later Neo-Platonists, Plotinus says that our souls are always connected to the universal intellect and that we never really fall away.

When you're seeking after bodily pleasure of food and drink for example, this is going to prevent you from doing what you should be doing which is contemplating.

In fact one of the things about Plotinus is that he maybe not singlehandedly, but I think more than anyone else, killed off the variety and dissension among the philosophical schools of antiquity.

I think it's important to realise that what happens in Neo-Platonism beginning with Plotinus and Porphyry and then going on for the next several centuries, is a real kind of contest for the ideas and convictions of the intelligentsia of the later Roman Empire. So that you have Christians slowly converting more and more powerful people until of course actually Constantine and then other emperors after him, become Christian, and the empire becomes a Christian empire rather than Pagan empire.