"The good of the grace of one soul is greater than the good of the nature of the whole universe"
- St Thomas Aquinas Ia IIa, q.24, a. 3, ad 2

— A Commentary on the First Part of St Thomas' Theological Summa

by Reginald Garrigou-Lagrange, O. P.


Question 10: The Eternity of God



State of the question. It is not, strictly speaking, a question here as to whether there is a difference, but it is asked what is the reason for this difference. Thus eternity and time are compared from on high, whereas in the first article the ascent of the mind was made by the way of investigation, from time to the definition of eternity. Now by the way of sapiential judgment, time is judged from the highest of causes, or from eternity as already defined. There are three difficulties: (1) It seems that eternity does not differ from time, because they occur together. Hence it seems that time is a part of eternity, just as an hour, which occurs along with a day, is a part of a day. In other words, the finite cannot coexist with the infinite, unless it is a part of the infinite, as several pantheists say. (2) According to Aristotle,(28) the now of time remains the same in the whole of time. Therefore it does not differ from the now of eternity. (3) Eternity, which comprises all time, seems to be the measure of all things inasmuch as they proceed from God, and so it does not differ from time.

Yet the reply is that time and eternity are not the same, because eternity is simultaneously whole, whereas time has a before and an after.

In the body of the article, St. Thomas shows that, even if time had neither beginning nor end, it would differ from eternity, inasmuch as it would consist of a succession of years and centuries, namely, of a before and an after; whereas only eternity is simultaneously whole. He even says that the difference, which is founded on the fact that time has a beginning and will have no end, is an accidental one, which means that it could as well not be so. Therefore the reason for the difference lies essentially in the fact that eternity is the measure of permanent being, whereas time is the measure of movement. The solution of the difficulties confirms this.

Reply to first objection. Eternity and time can coexist and yet time is not a part of eternity, because they are not of the same genus, but only analogically agree in point of duration. So the finite being and the infinite being can coexist, and yet the finite is not a part of the infinite, because they are not of the same genus; but they are alike in this, that being is predicated analogically of each. Infinite being is self-existing being, whereas finite being is participated being, and is not its own being. There is never any variation from this in the refutation of pantheism.

Reply to second objection. What sort of identity is there between the now of time and the whole of time as this differs from the identity between the now of eternity and eternity? The now of time is the same as regards its subject in the whole course of time, just as movement is measured by time; but it differs in aspect, for what is movable is first here and then there. On the contrary, the permanent now of eternity is absolutely the same as regards both its subject and its aspect.

St. Thomas says with profundity of thought in this article: "The flow of the now as alternating in aspect, is time," just as the progressive passive actualization of the movable is movement. When he says that the now differs in aspect in the whole course of time, he does not mean that alternation is merely according to aspect and is not anything real. He is speaking, as he does in one of his commentaries,(29) in which he says that terminative transitive action and passion are the same as movement, but differ in aspect, inasmuch as action is movement as coming from an agent, and passion is movement as found in the movable. This means to say that they are the same as regards their subject, but that they differ according to their constitutive aspects, and so, according to the Thomists, there is a modal distinction between terminative action and passion. In like manner, St. Thomas says: "Man and white are the same in subject, and different in idea; for the idea of man is one thing, and that of whiteness is another." (30) He does not mean that whiteness, which is an accident, is not really distinct from the substance of man; but it can be said that this man is white, so that in this proposition as in every affirmative proposition, "the predicate and the subject signify the same thing in reality." (31)

There is a most manifest difference, at least in the abstract sense, between the passing now of time and the permanent now of eternity. The passing now of time comes within our experience, but the permanent now of eternity does not. Hence eternity is less intelligible to us than time, but it is more intelligible in itself. For in itself the now of time is scarcely intelligible, because it is almost nothing, is among the inferior limitations of being, is always changing, and when it is said that the present moment is, it already is not.

On the contrary, the now of eternity is always permanent, always is; in fact, it is the self-subsisting Being, inasmuch as God is His eternity.

Reply to third objection. The being of corruptible things, because it is changeable, is not measured by eternity, but by time. However, as we remarked above, since created things are not passively produced in themselves, but are present in God as the terminus of His eternal action, they are measured by eternity. Thus eternity is the measure of all measures and includes all times.



State of the question. The purpose of this question is to inquire into the proper meaning of aevum (age). This word, which is still one in common use, as when we speak of the Middle Ages (medium aevum), means, among Latin authors, either a certain age of the human race or that of some man - thus the first age corresponds to the period of youth, whereas full age corresponds to maturity - or perpetual duration (Varro). Aeviternal means also perpetual.

The Scholastics. say that aeviternity is "the measure of spiritual substances." Previous to this, St. Augustine (32) had said that we must admit a certain intermediate duration between eternity and time. This intermediate duration is difficult to conceive. It is, indeed, not so intelligible in itself as eternity, and not so intelligible to us as time, because it does not come within our experience. The principal difficulty that confronts us in distinguishing between aeviternity and time is that, if aeviternity is not eternity, then it is not simultaneously whole. Therefore it has a before and an after, and hence it does not seem to differ from time.

Yet the reply is that aeviternity differs from time and from eternity, as the mean between them.

The proper reason for this difference is not given by some, whose conception of eternity is more material than formal. They said that eternity has neither beginning nor end; that aeviternity has a beginning but no end (inasmuch as the angels were not created from eternity); that a time has both beginning and end. But this difference is accidental, because even if aeviternal things had always been, aeviternity would be distinct from eternity.

Others said that aeviternity differs from eternity, in that it has a before and an after; and that it differs from time, because it has neither youth nor age. But this involves a contradiction; for if aeviternity has a before and an after, it also has youth and age. It would have youth when the after part appears, and age in the receding of the first part. In like manner, if the aeviternal thing were not subject to youth and age, this would be because it is immutable, and hence it would have neither before nor after.

But the true difference consists in this, that aeviternity is the mean between eternity and time, because it is unchangeable, though it has changeableness annexed to it. It is proved as follows: In so far as anything recedes from permanence of being, it recedes from eternity. But mutation, whose measure is time, recedes more from eternity, than does immutation, to which, however, mutation is annexed, whose measure is aeviternity. Therefore aeviternity is the mean between eternity and time.

St. Thomas explains this in his reply to the first objection, in which he says: "Spiritual creatures, as regards successive affections and intelligences, are measured by time (not by continuous time, however, such as solar time, but by discrete time) .... But as regards their nature, they are measured by aeviternity, and as regards the vision of glory, they have a share of eternity."

Thus aeviternity is the measure of an immutable thing, which in its operations, however, is connected with change. Hence aeviternity has not in itself either before or after, as stated in the second opinion; but before and after are compatible with it.(33)

Scotus objects to this, remarking that at least several angelic operations are not successive but permanent. Hence they are measured, he says, not by discrete time but by aeviternity.

Bannez replies by saying that there are three kinds of angelic operations. (i) There are those angelic operations that are connatural to the angel and unceasing. These are measured by aeviternity, as St. Thomas himself says.(34) Thus the angel's natural knowledge of himself, of God as the Author of nature; and his natural love of himself and of God are of this first kind. (2) Then there are those immanent angelic operations that are not permanent but successive. These are measured by angelic discrete time. This time refers to the number of angelic thoughts, as St. Thomas states farther on as follows: "If the time of the angel's motion is not continuous, but a kind of succession of nows, it will have no proportion to the time which measures the motion of corporeal things, which is continuous, since it is not of the same nature." (35) Thus one angelic thought constitutes one angelic moment, and it can last for several years of our continuous solar time. Thus with those saints who are still wayfarers, when they are in ecstasy, there is a sort of immobile and loving contemplation that takes place in the summit of their soul, and sometimes this lasts for several hours of our continuous time. (3) There is finally, the virtually transitive operation of the angel by which he locally moves bodies. It is measured terminatively by our continuous time, in that the movement of this body is measured by solar time and it lasts, for instance, half an hour.

Doubt. How can aeviternity be simultaneously whole, although before and after are compatible with it, as St. Thomas says in his reply to the second objection?

The difficulty is that if aeviternity is simultaneously whole, it contains time eminently, just as eternity does. Such being the case, the angels would have a natural knowledge of future contingent things, and they would not have to wait for their realization.

St. Thomas replies to this by saying that aeviternity is simultaneously whole inasmuch as the angel's substantial being is immutable, and is not the subject of succession.(36) However, aeviternity does not contain time eminently as eternity does, because angelic being does not contain eminently the being of mutable things, as the first cause in its action contains all things that are. Moreover, as it has been remarked, the angelic knowledge of particular things is not measured by aeviternity but by discrete time. Thus angels cannot have a natural but only a conjectural knowledge of future contingent things. Hence aeviternity coexists with our continuous time somewhat as an immovable stone placed in a river, coexists with the various parts of the flowing water. But eternity is like a mountain peak from which the whole river is seen by one glance. And so this proves that aeviternity is the mean between eternity and time.



State of the question. The purpose of this article is to compare the unity of aeviternity of all aeviternal things, namely, of angels and of disembodied spirits, with the unity of time of all sensible movements

The reply of St. Thomas is that, according to the truer opinion, there is one aeviternity for all subordinate aeviternal things, just,. as there is one time for all subordinate sensible movements in the universe. For it is evident that to form an idea of the unity of duration of spiritual beings, we must first consider the unity of duration of sensible things. But the unity of duration of sensible things or the unity of continuous time depends on the fact that the movement of the first movable (we are speaking of the sun in our solar system) is supposed to be uniform. Thus solar time is the intrinsic measure of solar movement and the extrinsic measure of other subordinate movements. Thus time is one and continuous. By analogy, therefore, there is one aeviternity, inasmuch as there is subordination among the angels, and thus the being of all subordinate aeviternal beings is measured extrinsically, as it were, according to the intrinsic measure of the first aeviternal being, or of the highest angel. This opinion presupposes that the angels are not equal, but are subordinated, or that they proceed from God in a certain degree and order.(37)

It must be observed that unity of continuous time presupposes, but does not apodictically prove as many think, that the apparent movement of the sun is uniform, or that the real movement of the earth around the sun is uniform, that is, always of the same velocity.

But this, as many think, is not apodictically true, for there would have to be first a fixed unity of time which is reckoned according to a presupposed uniformity of movement. Nevertheless the hypothesis of the uniformity of the sun's apparent movement is confirmed by the harmony that prevails between the various ways we have of measuring time, for instance, in the clocks we use.(38} Moreover, this hypothesis, which was already explicitly formulated by Aristotle,(39) is more in conformity with the simplicity of the laws of nature than is the hypothesis of some non-uniform but accelerated or retarded movement, or of one that is sometimes accelerated and sometimes retarded with compensation, whose velocity is not always the same. Therefore the truer opinion is that there is one time and one aeviternity.

Yet the fourth objection in this article states that things not dependent on one other, do not seem to have one measure of duration. But aeviternal things do not depend on one another, for one angel is not the cause of another angel. Consequently there is not only one aeviternity.

St. Thomas replies by saying: "For things to be measured by one, it is not necessary that the one should be the cause of all, but that it be simpler than the rest." Thus arithmetical unity is the principle of number, and the letter is the principle of unity for the syllable.

Recapitulation. And so we bring to an end this beautiful question of eternity, which is compared with other durations. From the foregoing we clearly see that the principle characteristic of eternity is not to be without beginning and end, but to be simultaneously whole, without succession and variation, according to a most perfect uniformity. Hence there is but one and permanent now of eternity. On the contrary, the now of continuous time alternates between the past and the future. Aeviternity is the mean between time and eternity, and so it is "simultaneously whole, but before and after are compatible with it," (40) according to a succession of thoughts in the angels. Finally, in the discrete time by which these successive thoughts of the angels are measured, there are several standing, successive nows; so that one angelic thought or contemplation is present in the same moment of time, and a subsequent thought in another, without any continuous time intervening; whereas in our time two moments are always separated from the one time that is infinitely divisible. Thus also, while the angels move bodies locally, as stated farther on, "the time of an angel's motion can be non-continuous; so an angel can be in one place in one instant, and in another place in the next instant without any time intervening." (41)

Wherefore "the standing now" of eternity is like the apex of a cone, the base of which would represent the successive parts of time. But between the apex and the base is aeviternity to which change is annexed, and discrete time consisting of several successive standing nows. Thus a more profound knowledge is acquired of the definition of eternity as formulated by Boethius, who says it is "the simultaneously-whole and perfect possession of interminable life." (42) The unitive life of the saints, already here below, approaches this eternity and especially so does the beatific vision of which participated eternity is the measure.

Index Top


28. Physics, Bk. IV, chap. 11.

29. Ibid., Bk. III, lect. 5

30 Summa theol., Ia, q. 13, a. 12.

31. Ibid.

32. Book of 83 questions, q.72.

33. Cf. ad 2um.

34. Quodl., q.5, a.7.

35. Summa theol., Ia, q.53, a.3 ad 1um.

36. Quodl., q.10, a.4; also reply to third objection of this article.

37. Summa theol., Ia, q.47, a.2.

38. Cf. Lechalas, Espace et temps, p. 84.

39. Physics, Bk. VIlI, chap. 14; Metaph., Bk. X, chap. 1.

40. Summa theol., 1a, q. 10, a. 5 ad 2um.

41. Ibid., q.53, a.3 ad 3um.

42. De consolatione, Bk. III, pros. 2.



"To think of oneself as nothing, and always to think well and highly of others is the best and most perfect wisdom. Wherefore, if you see another sin openly or commit a serious crime, do not consider yourself better, for you do not know how long you can remain in good estate. All men are frail, but you must admit that none is more frail than yourself. "

Thomas á Kempis

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"Lord, take from me everything that hinders me from going to You. give me all that will lead me to You. Take me from myself and give me to Yourself."

St Nicholas Flue

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"He who wishes to be perfectly obeyed, should give but few orders."

St Philip Neri

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