CHAPTER II. The Eternity of God.

Thesis XXIII. -- God is eternal in the strict sense of the word.

148. The word "eternal" taken in a wider sense signifies endless existence, though that existence may have a beginning, and may run through various successive phases. Thus, the life of men after the day of the general resurrection will be eternal, though not without successive mental acts and bodily movements. It is called eternal simply because it will never cease.

In its strict sense the word eternity implies an existence which is essentially without beginning, and without end, and without any successive phases of being. We beg the reader not to overlook in this definition the word essentially. If we imagine a spirit created by God from eternity, and preserved by His infinite power for ever without any internal change, the existence of such a spirit would be indeed without beginning and end, and without successive phases of being, but it would not be eternal in the strict sense of the word. And why not? Because the essence of that spirit would have no existence of itself, but would be indebted for its existence and its boundless duration to the free choice of the omnipotent God.

From the definition of eternity just given it is evident that the term, if predicable at all in its strict sense, is predicable of God alone. No creature can be essentially without beginning and end and internal succession. Not essentially without beginning, for there is no reason why any creature must be created from eternity. Not essentially without end; for God may withdraw from the creature His preserving power. Not essentially without internal succession, for at least the infinite power of God can cause in it a new phase of existence.

149. Is then God Himself eternal in the strict sense of the word? Yes; because as the First Cause, and the only source of all possible being, He must exist with absolute necessity, and therefore can have no beginning. Absolute necessity of existence must be identical with His essence, on account of His simplicity, which we have proved to be not only physical but metaphysical (Th. VIII. § 61, seq.); and therefore it is impossible that He should cease to be. His existence is unchangeable (Th. XXII.); therefore it cannot contain any different successive phases or modes of being.

Boëthius, who flourished about A.D. 500, in his work, De Consolatione Philosophiae, thus defines eternity^{1} "Eternity is a simultaneously full and perfect possession of interminable life." What in our definition was implied by the terms "existence essentially without beginning and without end," is expressed by Boëthius more explicitly in the phrase, "possession of interminable life." Indeed, as eternity proper belongs to God alone, it is identified with the highest life conceivable, the self-activity of infinite Intellectual Will. This life is "interminable," or boundless, because it endures of absolute necessity. It is "simultaneously possessed" in its fulness and perfection, because, being infinite, it is neither capable of development nor liable to defect. As it is now, so it has been always in the past, and will be always in the future. Coexisting with all assignable moments of time, the eternal God is above any of our measures of the contingent duration of created being. In Him, therefore, is neither present, nor past, nor future. As Boëthius expresses it, Nunc fluens facit tempus, nunc stans facit aeternitatem -- " The passing now makes time, the standing now makes eternity."^{2} In other words, the duration proper to the eternal Being must be conceived as one everlasting state, whereas the duration of temporal being is liable to a succession of states really distinct from one another.

150. Between temporal and eternal duration there is a duration intermediate, which, for the sake of distinction, is called by the scholastics, aeviternal duration, or aevum. It is the duration of created spirits. Both time and aevum are contingent durations, dependent upon the freewill of the one eternal Being. But while time is made up of successive states or phases of being, aevum does not imply any succession. A created spirit may be annihilated, but the specific spiritual being proper to it cannot be changed; consequently there is no succession in it, as regards its substantial perfection. Nevertheless, spirits are not quite above time, or succession of states in their existence; for, though the specific perfection of their substantial being is unalterable, they can still pass from one thought and volition to another, and the creator may cause in them now one, now another accidental perfection. Their essential being is above time, but they are liable to accidental modification of temporary duration. The duration, called time, belongs most properly to matter, which changes as well in its substantial as its accidental perfection.

St. Thomas expresses the difference between time, aevum, and eternity briefly in this way: "Time has an 'earlier' and a 'later'; aevum has no 'earlier' and 'later' in itself, but both can be connected with it; eternity has neither an 'earlier' nor a 'later,' nor can they be connected with it."^{3}

In other words: Time is made up of a series of changes in a substantial stratum, or in the accidental state of a complete substance; aevum is not itself a series of either substantial or accidental changes, but in the finite incorruptible substance, of which it is the duration, there may be accidental changes; Eternity is the duration of a Being above all change, whether substantial or accidental. As the duration called eternity is nothing really distinct from the Eternal God Himself, we are right in saying that all and each of the successive events which happen in this world are coexistent with the whole of eternity considered in itself. But none of them is coexistent with the whole of eternity in so far as eternity is considered in its relation of coexistence with preceding or following events, for the simple reason that each temporary event is a passing reality, whilst eternity is, so to speak, a standing reality, the everlasting Being whose Essence is Existence, abiding always the same with absolute necessity. The works of His hands are the heavens. They shall perish, but He shall continue; and they shall all grow old as a garment, and as a vesture shall He change them, and they shall be changed; but He is the self-same.^{4}

151. Hence we gather the solution of difficulties against the eternity of God, such as the following:

Two things, the duration of which wholly coincides with the whole duration of a third thing, must coexist with one another. But the Deluge and the Franco-German War are two things, the duration of which according to the exposition given, wholly coincide with the whole duration of God. Consequently, whilst the Germans were fighting against the French, the earth was covered with the waters of the Deluge.

This difficulty, though commonly urged, need not detain us long, after the explanations given of the strict contents of the meaning of time as distinguished from duration. Both in God and in created things there is duration, for duration in itself is pure perfection. But the Divine duration, since it is a changeless persistency in existence, does not in itself offer any means of distinguishing before and after. When, however, substances are created whose being is liable to successive phases of existence, they, at each period of their existence, coexist with God, they last, whilst the entire being of God is persisting. But this clearly does not cause them all to be contemporaneous with one another, since although coexisting with the entire being of God, they are not coexistent with the entire duration of God.

The same difficulty and the same solution will present themselves when we compare the Divine immensity with the localization of bodies. Since God is everywhere, and everywhere whole and entire, wheresoever any extended substance is placed it is in the same place with the whole of God: but it would be absurd to conclude therefore that all bodies are coincident in point of place.

{1} "AEternitas est interminabilis vitae tota simul et perfecta possessia." (V. Prosa vi.)

{2} De. Trin. c. iv.

{3} Tempus habet prius et posterius; aevum autem non habet in se prius et posterius, sed ei conjungi possunt; aeternitas autem non habet prius neque posterius, neque ea compatitur." (St. Thomas, Sum. Theol. 1a. q. 10. art. 5. in corp.)

{4} Cf. Heb. i. 10-12.