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The Domestic Aquinas Project

Making the Summa Applicable to Families

Prima Pars

Question 10: The Eternity of God (6 Articles)


Article 1:  The Definition of Eternity


Structure of the Argument:

In order to understand eternity we have to understand time.

Time is simply the measurement of movement.  Movement has a beginning and an end. Movement has a before and an after.  Time measures this.  Thus, time isn't something exists in it's own right. It is only there if there is movement.  We use the movements in the galaxy and the stars by which to measure our night and day.  We use mark a beginning and an end with time in the Olympics. And so on and so forth.

The conclusion is that if there is no movement then there is no time.  This is then eternity.  Eternity would be a perpetual moment or a forever present.  No beginning. No end. No movement from here to there.  

The definition given to us by Boethius is as follows:

"The simultaneously whole and perfect possession of interminable life."  In other words, eternity is without parts (before and after) and is thus without succession and is it has no end or is interminable.  

Family Take Home:


Eternity is a concept that is difficult to teach children. 

But it is important especially later in understanding how

God works within time.  For this article it is enough to

explain that eternity has no beginning and no end and

is therefore an eternal moment. 


To explain this better: imagine sitting on a bench on a

country road and watching from morning till dusk all

that passed by on that road.  We would see things from

the beginning to the end.  Now imagine God sitting on that bench.  He would see all things at once and be wholly present to them all at once. Why? Because He is eternal like eternity: without beginning and without an end.

Bench on Autumn Leaves

Article 2:  Is God Eternal?


Structure of the Argument:

Very Simply: if God is immutable and immovable then He must eternal.  It belongs to Him to be eternal as He is the only one who cannot be moved (for He is everywhere).  

Family Take Home:


God is not measured by eternity as if eternity were some sort of measuring stick.  He IS eternity for He His own being and the author of Himself.  He simply IS.  We only use phrases and words like 'before' and 'after' with God because they help our finite

minds to understand Him.  

What is interesting here for the family is that God is wholly

present to the past, present and future.  So a child may ask,

why do we pray the Christ-child when Jesus has grown up

and gone to Heaven?  We can pray to the Christ-child for

the Christ-child was wholly present to us when the 2nd

person of the Trinity became enfleshed.  In other words,

Jesus is God.  Thus, Jesus is eternal.  So, as a baby, He was

present to all things past, present and future.  That means,

as a baby, He was present to me, now, in the future.  And if praying to the Child King helps to be humble, celebrate the Christ-Mass time and draw us closer to Him, then we do so.

Nativity Scene

Article 3:  Is God the only one that is eternal?


Structure of the Argument:

Again, because God alone is immutable, He alone is eternal.  

However, there are things that participate in His eternity.  Angels, for example, participate in His eternity.  They have a beginning, but they will never die (for they have no bodies).  The fires of Hell are said to be 'eternal' (Mt. 25:41).  Hell is eternal insofar as it doesn't end.  However, there may be movement or change in Hell.

Family Take Home:


Why do we believe in 'life everlasting' as we state in the creed each Sunday?  Does this mean we will become eternal?  

When we die in the grace of God, as His sons, we participate in His divinity.  II Peter 1:4 states we will "participate in His divine nature."  God's nature is eternal.  Thus, we'll participate in it insofar as we will leave forever.  We are not eternal, but we participate in God's eternalness.

Article 4:  Does Eternity differ from Time?


Structure of the Argument:

Time measures movement be it change, growth, destruction, speed and so forth. It generally has a beginning and an end. 

Eternity however measures an abiding existence or a permanent whole that doesn't change. 

Time has a present now that continually begins and ends.

Eternity is a perpetual now without a beginning and an end.

Family Take Home:


The take home here has less to do with eternity and more

to do with time. It is important for our children to

understand that time in itself doesn't exist. It is simply the

tool we use to measure movement or change. If there was

no movement or change there would be no time.  We assign numbers based on the movement of the heavens to help us track our movement and change.  With God, there is no time.  He is permanently present to our past, present and future. In this way that He knows us, He is the one Person that we can trust implicitly. And as the Father that He is, He works out all things together for the good of those that love Him (Rom. 8:28).

Brass Clock

Article 5:  The Difference of Æviternity and Time


Structure of the Argument:

Time measures movement be it change, growth, destruction, speed and so forth. It generally has a beginning and an end. 

Eternity however measures an abiding existence or a permanent whole that doesn't change. 

Time has a present now that continually begins and ends.

Eternity is a perpetual now without a beginning and an end.

Æviternity  is the mean between eternity and time. It accounts

for beings such as angels who don't have bodies, yet they can

change. The have choice, they can't be every place at once

(like God) so they have movement, and they can grow in

knowledge and love.  They are outside of time, but not eternal.

Thus, St. Thomas states they are in Æviternity.

Family Take Home:


When discussing Heaven with our children it is important to note, that though we participate in eternity, we'll not be eternal.  Thus, there will still be change.  We will not know everything upon entry into the Eternal Kingdom, but will learn forever because God is infinite.  So Heaven will not be boring. We will be learning continually, exploring and moving around in our glorified bodies (more on this in the tertia pars) but, our will will be at rest. All our desires will be at rest for we will be completely fulfilled in Him.  What does this mean? My boys always say that if they could have a room full of Lego they would be happy.  But they wouldn't, because they would always desire more. But in Heaven, all desires will be filled.  Forever.


Article 6:  Is there only one Æviternity?


Structure of the Argument:

In order to answer the question, St. Thomas takes his understanding of time first and then applies it to Æviternity. 

Time is one.  Meaning it does not change how it measures movement and growth with every different movement.  There is a consistency in time because it is derived the movement of the heavens.  From this movement, we know what time it is and use time within this parameter to measure other movements and changes.  For eg: my daughter is 13 yrs old.  I know this because I know the year she was born.  Her measured years come from knowing first the amount of days are in a year and how long the rotations of the heavens take.

Æviternity, is simpler than time and therefore must be one as well.  And as time derived from one source, so also Æviternity.  "Æviterniteral things are measured by the first Æviterniternal thing."  Though, at this point, Thomas doesn't tell us what that is.

Family Take Home:


I actually recently had this conversation with my daughter, that is to say that she was trying to understand the difference between time and eternity.  In regards to time and Æviternity being one, it is important to note the source of time.  Time, though it is an accident of movement, isn't arbitrary and we don't change how we measure time with each different movement.  It is clear that a second is a second and an hour is an hour.  Thus, we can know with certainty the ages of things, how long things take to get done, and so forth.  We have this certainty because the heavens that are providing the rotations and are giving us night and day have certain movement.  

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