The soul is the principle of life, and it's also something much closer to our own awareness and consciousness of our existence because fundamentally for Plotinus what we are is souls, we're not intellects.

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.

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

If you think about for example, proportionality and beauty, things like that, these seem to be some kind of representations of a kind of unity.

Soul puts the determination or forms or images of forms, into matter.

In fact Plotinus does believe in divine providence, though when he talks about divine providence, he talks about that providence being exercised by the intellect and the soul of the world, rather than the One.

The importance of Plotinus is not only his own philosophical ideas which are quite interesting, but his historical impact as the founder of neo-Platonism which is the main philosophical tradition of late antiquity.