“Even if I grant you there needs to be a necessarily existing entity to ground all being, you still haven’t proved that this is the God of the Bible.”
Agreed. So what’s the problem here?
The real problem with this common objection is it is yet another demonstration of the lack of awareness of classical theism in our modern culture.
God is not just an arbitrary definition or a tautology that theists create to rationalize their belief system. God is the logical conclusion of many arguments from classical theism. Building off of the conclusions of a necessary being, there are many more arguments that show God must have certain attributes.
In this post, I will 1) give a summary of some of the most commonly attributed qualities to God, 2) demonstrate why these attributes are necessary conclusions and 3) demonstrate that these are the same qualities we see the Bible attribute to God.
In his book The God Delusion, Richard Dawkins put forth this same objection in responding to the Five Ways arguments of Thomas Aquinas:
“Even if we allow the dubious luxury of arbitrarily conjuring up a terminator to an infinite regress and giving it a name, simply because we need one, there is absolutely no need to endow that terminator with any of the properties normally ascribed to God: omnipotence, omniscience, goodness, creativity of design, to say nothing of such human attributes as listening to prayers, forgiving sins, and reading innermost thoughts.” 
Dawkins demonstrates here that he clearly hasn’t read the Summa Theologiae or studied Aquinas’s thought in any detail. If he had, he would realize that Aquinas’s Five ways are just a short summary of many complex arguments that he had given elsewhere. The word “summa” is Latin for “summary”, after all.
After Aquinas lays out his summary arguments in the Five Ways, he then spends a great many pages going over how a necessary being must have certain attributes. These are the very attributes that Dawkins claims Aquinas does not show God has. It is unfortunate that the attributes of God are not more well known, as they can help illuminate many common misunderstandings people have of God.
Why Study the Attributes of God?
The study of God’s attributes is one of the key areas of study in classical theism. One reason is it shows us how wholly “other” God is from creation.
I often find that people have too small of a view of God, both Christians and non-Christians alike. They often picture an anthropomorphic God, a superhuman in the sky, like Zeus or Odin. This is not the picture of God that the Bible or classical theistic arguments describe.
16For in Him all things were created, things in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities. All things were created through Him and for Him. 17He is before all things, and in Him all things hold together.
Sometimes non-believers will claim we all are atheists about the other 10,000 gods that other religions claim exist, they just go one god further. Studying the attributes of God is helpful here to see how comparing God as revealed in the Bible to the other gods of human mythology is a huge category error. None of the other gods of human mythology make the claim to be the ground of all being. They all are in some sense finite, next to the infinite God of the Bible. The attributes of God are helpful to even begin to hint at what it means for an infinite being to exist.
A couple other reasons the attributes of God are important are that though God in many ways is beyond all comprehension and human understanding, studying His attributes shows us that the conception of God is still rationally coherent and does not contain any contradictions. Also, studying the attributes of God does point us to the attributes that can be found in scriptures. This is another piece of evidence that confirms the God of the Bible is necessary, real, and worthy of worship.
Starting Point: Pure Act
All discussion of the attributes of God starts with showing the necessity of His existence as pure actuality. He is the ground of all being.
Another way to explicate this doctrine is to appeal to the Act/potency distinction. For Thomas, the first reality whether construed as unmoved mover, uncaused cause, or necessary being, must be characterized as actus purus, pure energy or actuality. But essence functions as a principle of potency, since it delimits the actus ascending the act of being, somewhat in the manner that matter sets a limit to form. Thus my humanity determines that I am a very particular type of being relating to my existence as potency to act. Therefore, in the actus purus of God there can be no principle that delimits the divine act of to be. Or, to state the same thing there can be no distinction between essence and existence in God. As David Borel, the theologian and philosopher from Notre Dame put it, to be God is to be “to be”. In regard to any creature from an archangel to a stone no such formula could possibly be applied.
–Bishop Robert Barron
Because God is pure act and cannot contain any potencies, out of God’s necessary existence flow out some necessary attributes.
Several attributes seem to follow immediately and obviously from God’s being Pure Act. Since to change is to be reduced from potency to act, that which is Pure Act, devoid of all potency, must be immutable or incapable of change (STI.9.1). Since material things are of their nature compounds of act and potency, that which is Pure Act must be immaterial and thus incorporeal or without any sort of body (ST I.3.1–2). Since such a being is immutable and time (as Aquinas argues) cannot exist apart from change, that which is Pure Act must also be eternal, outside time altogether, without beginning or end (STI.10.1–2). 
We will now move our discussion to 8 of the most commonly listed attributes of God. These are the eight attributes that Aquinas immediately goes into a discussion of after laying out his arguments for God’s existence in the Five Ways.
1) Simplicity, 2) Perfection, 3) Goodness, 4) Infinity, 5) Ubiquity, 6) Immutability, 7) Eternity, and 8) Unity.
To say God is simple is certainly not to say that God is easy to understand. This is one of the more complex ideas in all of theology.
God is simple because he is non-composite or without parts.
Divine simplicity is one of the core teachings of classical theism and has been affirmed by many theists throughout history. The reason for this is that divine simplicity is a necessary conclusion of God’s being given He is pure act.
At the core of classical theism is the notion of divine simplicity”the idea that God is non-composite or without parts. This is a doctrine having its philosophical roots in Plato and Aristotle and defended by pagan, Jewish, Christian, and Muslim thinkers as diverse as Philo of Alexandria, Irenaeus, Clement of Alexandria, Athanasius, Plotinus, Augustine, Boethius, Anselm, Maimonides, Avicenna, Averroes, Aquinas, and Scotus. The doctrine is the de fide teaching of the Catholic Church and is endorsed by many Protestant theologians. The point of all this name-dropping is to emphasize how absolutely central the doctrine of divine simplicity is to the mainstream Western tradition in philosophical theology. 
The reason God cannot have any parts is if He did, there would have to be a cause for His parts. There would need to be some way which His parts came together to be God. All things that have parts have potentials which need to be actualized (caused) if they are to really exist.
You can think of any object in the natural world for an example. A car is composed of parts, each of which all has a cause for their existence. Natural objects, also, are made up of parts with potentials. Water, for instance, is made up of Hydrogen and Oxygen. These constituent elements contain within in them the potential to become water when joined together. There needs to be a cause that actualizes these potentials.
Conversely, God is pure act. This means that He contains no potentials. Since all things with parts contain potentials, God must not contain parts. Likewise to even be made up of matter is to have potentials, so God must, therefore, be immaterial. An immaterial being without parts is divine simplicity. This is what the classical theist means by the word God.
God also cannot have a distinction between His essence (what it is) and existence (that it is) like all other things do. For instance, I can say that a specific horse has both an essence (what it is) and existence (that it is). I can also say that a unicorn has an essence (what it is), but that it does not have existence (it is not real). If there were no distinction between essence and existence, this would mean anything that has an essence would by necessity also exist. Unicorns or Harry Potter would by necessity need to be real, then.
God, on the other hand, cannot fail to exist. This is because His essence is to exist. Essences need existence added to them to exist. Until they have existence, they are just potential essences. Since God has no potentials, He just exists.
Furthermore, God is also simple because he does not belong to any genus. He is wholly other from everything that exists. A genus is a class; it is the part of a definition that all members of a same class share. The differentia is the part or a definition of something that is different from the other members of the class. For example, shape is a genus, and triangle and square are the species; their differentia being the number of sides and angles contained in them.
God cannot be a genus because he would have to have some aspects of Him that would differentiate Him from other members of His genus. This would entail, again, that He has parts and potentials, and then He would no longer be the purely actual ground of all being.
God is therefore simple. God is being itself. God is “to be”.
God said to Moses, “I am who I am.” And he said, “Say this to the people of Israel, ‘I am has sent me to you.’”
2) The Perfection of God
God is perfect because He is the most actual thing in existence. Perfection is really another way of saying fullness of being.
Aquinas says in the Summa Theologiae that “a thing is perfect in proportion to its state of actuality, because we call that perfect which lacks nothing of the mode of its perfection.” ST I-II. Q4. A1
Since God is being itself (pure act), He is therefore perfect.
“Therefore you are to be perfect, as your heavenly Father is perfect.
3) The Goodness of God
God is being itself. Becuase being and goodness are convertible, God must be perfectly good as well.
In classical theism, there are transcendental entities that are considered to be convertible. This is to say that they are all the same thing looked at from different angles. Goodness, truth, and being are really the same thing. As God is being itself, He is also the highest good.
Give thanks to the LORD, for He is good, For His lovingkindness is everlasting.
Give thanks to the God of heaven, for his steadfast love endures forever.
For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life.
God shows his love for us in that while we were still sinners, Christ died for us.
4) The Infinity of God
If God contained any parts or potentials, he would have limits. Since God is in no way limited. He is, therefore, infinite.
“Jesus looked at them and said. ‘With man this is impossible, but with God all things are possible.’”
“Great is our Lord, and mighty in power; his understanding has no limit.”
“Do you not know? Have you not heard? The Lord is the everlasting God, the Creator of the ends of the earth, He will not grow tired or weary and his understanding no one can fathom.”
5) The Ubiquity of God
God is the purely actual actualizer of everything in existence. He holds everything in existence at each and every moment. As such, He must be present (in a sense) in each and every location throughout existence. God is immaterial, so this is not to say that He occupies space per se, but that He gives everything being that fills every space. Aquinas puts it this way, “indeed, by the very fact that He gives being to the things that fill every place, He Himself fills every place.” ST I-II. Q8. A2
“Can a man hide himself in secret places so that I cannot see him? declares the Lord. Do I not fill heaven and earth? declares the Lord?
“Where shall I go from your Spirit? Or where shall I flee from your presence? If I ascend to heaven, you are there! If I make my bed in Sheol, you are there! If I take the wings of the morning and dwell in the uttermost parts of the sea, even there your hand shall lead me, and your right hand shall hold me.”
“The eyes of the Lord are in every place, keeping watch on the evil and the good.”
6) The Immutability of God
To say that God is immutable is to say that He cannot change. Remember that to change is to actualize a potential. If God changed, He would then need to have potentials that are actualized. Therefore, God is immutable.
I the LORD do not change.
7) The Eternity of God
That which is pure act cannot have a beginning or an end. If it did, again it would have a potential that is actualized when it begins or ends.
“In the beginning God created the heavens and the earth.”
“I am the Alpha and the Omega, says the Lord God, who is and who was, and who is to come. The Almighty.”
“Even under his wings, Day and night they never stop saying: ‘Holy, holy, holy is the Lord God Almighty, who was, and is, and is to come.’
8) The Unity of God
The unity of God is similar in nature to the doctrine of divine simplicity. Because God cannot have parts, He must be one. Aquinas says “But He is supremely undivided inasmuch as He is divided neither actually nor potentially, by any mode of division; since He is altogether simple, as was shown above (I:3:7). Hence it is manifest that God is “one” in the supreme degree.” ST I-II. Q11. A4
There can also not be more than one purely actual being.
More generally, two or more things of a kind are to be differentiated in terms of some perfection or privation that one has and the other lacks. We might say, for instance, that this tree’s roots are more sturdy than that one’s, or that this squirrel is lacking its tail while the other has its tail. But as we have seen, what is purely actual is completely devoid of any privation and is maximal in perfection. Hence, there can be no way in principle to differentiate one purely actual cause from another in terms of their respective perfections or privations. But then such a cause possesses the attribute of unity—that is to say, there cannot be, even in principle, more than one purely actual cause. Hence, it is the same one unactualized actualizer to which all things owe their existence. 
As God is one, this also brings us to the conclusion that all these attributes are one in God. They really are all different perspectives of the same reality.
“Hear, O Israel! The LORD is our God, the LORD is one!
As we have seen, out from the very idea of a necessary being come necessary attributes. Dawkins is wrong, then, to claim that there is no reason to equate the God of Aquinas’s Five Ways to the God of the Bible.
We have also seen that these very attributes of God are found throughout the Bible. To me, this is further evidence from God that He is who He says He is. Or as He put it to Moses, “I am that I am.”
God is being itself. To be God is to be, “to be”.
Sometimes people will claim that ideas in Christianity are just borrowed from the other Near Ancient East religions (NAE) in ancient Mesopotamia. To compare God to the NAE gods, or any of the other 10,000 gods of human mythology is to completely misunderstand who Christians claim God is. When you study the philosophy behind the divine attributes, and especially compare these attributes to what the Bible states about God’s nature, we begin to see how uniquely other God is.
As finite creatures, we stand in such stark contrast to the being beyond all being. We should fear this being for His unfathomable power. He created everything out of nothing and holds everything in existence at every moment. And yet, we should love and worship this same being for He showed us His unfathomable grace, love, and mercy by taking our sins upon Himself on the cross.
10The fear of the LORD is the beginning of wisdom, And the knowledge of the Holy One is understanding.
8 But God demonstrates his own love for us in this: While we were still sinners, Christ died for us.
- Dawkins, Richard. The God Delusion. p.101. ↩
- Bishop Barron on divine Simplicity: Symposium with WLC Feb. 2018. 12:08 – 13:05 minutes. ↩
- Feser, Edward. Aquinas: a beginners guide. London: Oneworld. loc. 254 ↩
- Feser, Edward. Why Is There Anything At All? It’s Simple | Edward Feser. Firstthings.com ↩
- Feser, Edward. Five Proofs of the Existence of God Mobi (Kindle Locations 391–394). Ignatius Press. Kindle Edition. ↩