Reply Obj. 1: As Gregory says (Moral. xxxiii, 20) this is said of the devil as regards his members, whose hope will fail utterly: or, if it be understood of the devil himself, it may refer to the hope whereby he expects to vanquish the saints, in which sense we read just before (Job 40:18): "He trusteth that the Jordan may run into his mouth": this is not, however, the hope of which we are speaking.
Reply Obj. 2: As Augustine says (Enchiridion viii), "faith is about things, bad or good, past, present, or future, one's own or another's; whereas hope is only about good things, future and concerning oneself." Hence it is possible for lifeless faith to be in the damned, but not hope, since the Divine goods are not for them future possible things, but far removed from them.
Reply Obj. 3: Lack of hope in the damned does not change their demerit, as neither does the voiding of hope in the blessed increase their merit: but both these things are due to the change in their respective states. _______________________
FOURTH ARTICLE [II-II, Q. 18, Art. 4]
Whether There Is Certainty in the Hope of a Wayfarer?
Objection 1: It would seem that there is no certainty in the hope of a wayfarer. For hope resides in the will. But certainty pertains not to the will but to the intellect. Therefore there is no certainty in hope.
Obj. 2: Further, hope is based on grace and merits, as stated above (Q. 17, A. 1). Now it is impossible in this life to know for certain that we are in a state of grace, as stated above (I-II, Q. 112, A. 5). Therefore there is no certainty in the hope of a wayfarer.
Obj. 3: Further, there can be no certainty about that which may fail. Now many a hopeful wayfarer fails to obtain happiness. Therefore wayfarer's hope has no certainty.
On the contrary, "Hope is the certain expectation of future happiness," as the Master states (Sent. iii, D, 26): and this may be gathered from 2 Tim. 1:12, "I know Whom I have believed, and I am certain that He is able to keep that which I have committed to Him."
I answer that, Certainty is found in a thing in two ways, essentially and by participation. It is found essentially in the cognitive power; by participation in whatever is moved infallibly to its end by the cognitive power. In this way we say that nature works with certainty, since it is moved by the Divine intellect which moves everything with certainty to its end. In this way too, the moral virtues are said to work with greater certainty than art, in as much as, like a second nature, they are moved to their acts by the reason: and thus too, hope tends to its end with certainty, as though sharing in the certainty of faith which is in the cognitive faculty.