Reply to Objection 5: The succession of opposites in the same subject must be looked at differently in the things that are subject to time and in those that are above time. For in those that are in time, there is no last instant in which the previous form inheres in the subject; but there is the last time, and the first instant that the subsequent form inheres in the matter or subject; and this for the reason, that in time we are not to consider one instant, since neither do instants succeed each other immediately in time, nor points in a line, as is proved in Physic. vi, 1. But time is terminated by an instant. Hence in the whole of the previous time wherein anything is moving towards its form, it is under the opposite form; but in the last instant of this time, which is the first instant of the subsequent time, it has the form which is the term of the movement.
But in those that are above time, it is otherwise. For if there be any succession of affections or intellectual conceptions in them (as in the angels), such succession is not measured by continuous time, but by discrete time, even as the things measured are not continuous, as stated above (FP, Question [53], Articles [2],3). In these, therefore, there is a last instant in which the preceding is, and a first instant in which the subsequent is. Nor must there be time in between, since there is no continuity of time, which this would necessitate.
Now the human mind, which is justified, is, in itself, above time, but is subject to time accidentally, inasmuch as it understands with continuity and time, with respect to the phantasms in which it considers the intelligible species, as stated above (FP, Question [85], Articles [1],2). We must, therefore, decide from this about its change as regards the condition of temporal movements, i.e. we must say that there is no last instant that sin inheres, but a last time; whereas there is a first instant that grace inheres; and in all the time previous sin inhered.
