De Decalogo

But when the evil presses upon the soul, when it has not as yet taken up its habitation in it, but when it is only impending, being about to come and to agitate it, it sends before it agitation and suspense, as express messengers, to fill the soul with alarm; and this passion is denominated fear.

And when any one, having conceived an idea of some good which is not present, hastens to lay hold of it, he then drives his soul forward to a great distance, and extending it in the greatest possible degree, from his anxiety to attain the object of his desires, he is stretched as it were upon the rack, being anxious to lay hold of the thing, but being unable to reach it, and being in the same condition with those who are pursuing people who are running away, following with an inferior speed, but with unrivalled eagerness.