God has several “omni,” or “all,” attributes. These include omnipotence, omnipresence, and omniscience. We will also here address immutability, or that God never changes, seeing that many areas of modern culture attempt to refute this attribute.
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Omnipotence
God is omnipotent, meaning He is all-powerful. If He were not omnipotent, He would not be God, because some facet of creation would be more powerful than He. God is also omnipresent in creation, even though He exists outside of time and creation. Therefore, while He exists outside time and creation, He extends, so to speak, into creation. God is everywhere present because if He withdrew His presence from a certain place, that place would immediately cease to exist, for God is Existence Itself. The Second Person of the Most Blessed Trinity entered time and creation in a visible and fleshly way, becoming one of us in order to save us. He is still present everywhere in the universe, though nowhere (except in the Eucharist) is He present as He was when He was incarnate 2,000 years ago. The Lord is also omniscient, or all knowing. Of course, as in the case of omnipotence, if God were not omniscient, He would not be God because there would exist outside Him something more perfect than He in terms of knowledge, for everything except God Himself is known by someone or something else. God is also immutable, meaning that He does not change. Change implies a decrease or increase in perfection. But God has always been perfect and always will be, meaning that He cannot decrease or increase in perfection, and thus cannot change.
One classic and flashy atheist argument is that if God created a rock so heavy that He could not lift it, He would not be perfect because He would lack strength, but if He could not create such a rock, He would not be all-powerful. The problem with this argument is that it assumes that something greater than infinity can be created. Mathematicians know that nothing can be added to infinity. Anything added to infinity is just infinity. God cannot create a rock too heavy for Himself to lift because nothing can exist which Existence Itself does not encompass. This objection does not reveal a limitation of God, but is simply an absurd question that lacks proper understanding of infinity.
“Okay, then,” one might say, “but surely God is not omnipotent if He cannot sin!” But again, this approach lacks an understanding of the content in question. Sin is a manifestation of evil, and evil is not something positive (positive as in “that which is characterized by the presence of something,” not as in “good,” or “beneficial”). Evil is negative (as in “that which is characterized by the absence of something,” not as in “harmful,” or “detrimental”). For this reason, St. Augustine says that the essence of evil “is an absence of the good.” Therefore, to be able to sin is an imperfection, not a perfection, because sin is by its nature a lack of the good. God lacks nothing, and therefore cannot sin. Thus, His inability to sin supports His omnipotence.
Finally, some may say that since God shows mercy and forgiveness to us sinners, He is not omnipotent. If He were omnipotent, the argument goes, He would exercise His power of just punishment. However, God is able to show mercy because He is omnipotent. No force reigns over Him which would prevent Him from pardoning the sinner. He has completely free reign and power to do so. Moreover, the Lord does not have to punish the sinner, and not doing so would not be a limitation on His power, for His omnipotence does not depend on us. If it did, He would not be omnipotent. St. Thomas says that showing mercy is the foundation of all else, and by showing mercy, God leads His creation to Himself, their final end (ST I, 25.3).
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Omniscience
The Lord is omniscient because He is Wisdom – a property we ascribe particularly to the Son. But God does not know in the same way we know, for “as the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts” (Is 55:9). We come to know things in steps. We are not born knowing algebra, but we learn different mathematical principles which enable us to study algebra, and by studying algebra, we come to know it. God does not arrive at any knowledge, but rather he has always known everything and always will know everything. He knew all time and all creation before He created them. He knows by an “eternal, simple gaze” (St. Thomas). Everything is immediately available to Him and He comprehends it all in fullest measure.
Therefore, even when we come to know something, we do not know it as God knows it. For example, we understand certain things by abstraction. If we know what “dogness” looks like, we can recognize a dog when we see one. This dogness is called a universal, whereas an individual dog is a particular. Every dog is different, and so we can say that the particulars of dogs (i.e. different dogs) are different, but all dogs have the same dog nature. If they had a different nature, they would not be dogs. But God does not know in universals and particulars. He knows everything immediately and thus does not need to abstract anything to understand it or something else.
We can also think of God’s omniscience in terms of truth. We discussed earlier why there exists objective truth and that all truth pertains to God. In fact, God is Truth. It is illogical to assert that the Truth does not know everything, for everything that exists truly exists. Even if someone has a deceitful heart, God knows that that person truly has a deceitful heart. Moreover, he knows what truths, in particular, that heart is turning its back on, etc. Similarly, God knows all our thoughts, even our imaginations of unreal things. We are really having thoughts about the unreal. God knows everything through and through because He is Existence and Truth Itself, though He does not know in the same way creatures know, because He is perfect. He does not come to know things, for everything is immediately known by Him.
However, scripture seems to contradict God’s omniscience. There are multiple times in scripture when the Lord appears not to know something. After the Fall, He asks “where” Adam is (Gen 3:9). When His disciples tell Jesus who some say He is, He asks them Who they think He is (see Mt 16:15). But God knows what Adam and the disciples think, and He knows how they will respond to His questions. He asks them these questions in order to test them, for “the Lord scourges those who draw near to him, in order to admonish them” (Jud 8:27).
One may similarly assert that the Lord cannot be omniscient, for He cannot know what has not happened yet. From our perspectives in time, this objection applies. But God is outside of time and creation, and so in His eternal gaze, He immediately understands everything that has ever happened, is happening now, and will ever happen.
God’s knowledge of what all our actions will be can give the impression that He has predetermined us to salvation or damnation. But He has done neither. We have free will, and thus the Lord has not predetermined (in the sense of forced) us to do anything. Rather, while God knows what we will do, we do not, and it is up to us to choose Him at every moment of our lives, to death. We live in the moment, but for us the moment is a moment in time. For God, the moment is all time and creation in an instant. “[W]ith the Lord one day is as a thousand years, and a thousand years as one day” (2 Pet 3:8).
The Catholic view on predestination is that even though “predestined us to be adopted sons through Jesus Christ,” in the sense that He wants us to become His adopted sons, we have the ability to reject that call from God, because we have free will (Eph 1:5). Catholics, indeed all Christians, must focus not on whether God has predetermined them to salvation or damnation. He has done neither. We should focus on persevering to the end in God’s love. God knows all, for it is impossible that He Who is Existence Itself does not know all existence.
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Omnipresence
God is present everywhere in creation. He is spiritually present, as well as present by power. He is present everywhere spiritually because He is Existence Itself, and therefore everything that exists is constantly fueled by God. This does not mean that everything is God, not at all, but that God constantly keeps existence existing. If He “should take back his spirit to himself, and gather to himself his breath, all flesh would perish together, and man would return to dust” (Job 34:14). St. Thomas articulates it: “God is said to be in all things by essence, not indeed by the essence of the things themselves, as if He were of their essence; but by His own essence; because His substance is present to all things as the cause of their being” (ST I, 8.3).
In another manner, God is present everywhere by power. Because He has power over all, He can be said to be present everywhere. The Lord is present in all things because He is the efficient cause (the agent Who brings into being) everything, as a king is present everywhere by his power (ST I, 8.3, Respondio). Thus, in this way, God’s omnipotence implies His omnipresence. Likewise, St. Irenaeus says that “while [God] contains all things…He Himself can be contained by no one” (Against Heresies, Book II). If God were not omnipresent in creation, He would be contained, definable. But since we can only define God by similitude, God must be omnipresent in creation.
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Immutability
God is immutable, meaning He cannot change. He has always been and will always be the same, unchanging God, outside of time and creation, not subject to change. Because God exists outside time and creation, He does not experience the same changes that all creatures in time and creation do. Angels and the Blessed in Heaven, as well as the damned in Hell, do not change because they are also outside time and creation. They do not eat or sleep because they have no need for such activities. It is relatively simple to understand by reason that God cannot change.
But many scripture passages appear on the surface to indicate that God changes. For example, when the Lord is going to destroy Sodom and Gomorrah for their double transgression of rape and homosexuality, Abraham intervenes, asking the Lord that if there were but fifty people in the city, would He spare it. The Lord says He would. Abraham then asks the Lord if there were only forty people, if He would spare it, and the Lord again says He would. Eventually, Abraham gets down to ten people and the Lord agrees to save the cities for the ten. Perhaps it may seem as though Abraham reasoned with God and convinced Him to take pity on the righteous people in Sodom and Gomorrah. However, this is not the case because God cannot be subject to human persuasion, for He is “the way and the life,” and so cannot change the way or the life to mean something else than what it has meant from all eternity (Jn 14:6). Instead, this language instead puts Abraham’s plea in a relation to God that we can more readily comprehend. Perhaps the Lord may not have destroyed the righteous in the city, but if He was going to, He was waiting for Abraham to intervene. God, in His Providence, sometimes wills for men to intercede for others, so that He can work through them, because He wants us to learn to love Him, similar to how He wants us to come to the truth in stages and so allows for the Church to understand more about truth over time.
Just before this passage, the Lord appears to deliberate whether or not to “hide from Abraham” that He will destroy the cities (Gen 18:17). But this language is figurative. The Bible again tries to convey a truth to an incomprehensible truth to us. Therefore, the Holy Spirit, through the sacred authors, makes it seem as though God is deliberating. He probably does this to set up the next passage wherein the Lord waits for Abraha, to ask Him to spare Sodom and Gomorrah. But in reality, God does not need to deliberate about anything, because He knows everything instantly. He has all knowledge. “Even before a word is on my tongue, lo, O Lord, thou knowest it altogether.” (Ps 139:4). God decided from all eternity to destroy Sodom and Gomorrah, but to allow Abraham to intervene and to spare the cities if ten or more righteous people inhabited them, just as He knew exactly what He would do regarding everything else, from before all time.
The authors of scripture, especially of the Old Testament, often used more anthropomorphic language than we do now because they had a less perfect conception of God than those who have Christ’s light. While they could reason that God was outside of time and creation, they could not conceive of nor make certain logical inferences based on that information. Even now, we cannot understand what being outside of time and creation feels like because our natures are limited to understanding things in terms of time and creation. But we do have enough understanding to reach certain conclusions about God based on His subsistence outside of time and creation, such as that God does not change.
Whenever we hear of God repenting from His ways or apparently deliberating, that does not mean that He actually deliberates or changes His actions based on new information. Rather, these passages are instances of figurative language used to convey a truth to us which we cannot comprehend.