The first article of the Creed presumes that God exists and also affirms the uniqueness and unity of God. This avoids two errors: polytheism and dualism on the one hand and monism on the other. The first commandment is the correlative of this article of faith: "You shall have no other God before me".
This fifteenth lesson of the "Sunday Catechism", after having treated at length the "Creed" as an act of faith, now begins to examine the first article of the Creed which in the Latin version reads: "Credo in unum Deum", which means "I believe in one God" or “I believe in the one and only God”.
PREMISE. This is a series of Catechism lessons and not a treatise on philosophical or systematic theology; therefore we will not dwell on all the implications involved, albeit wonderful and important, of this affirmation according to natural or philosophical theology.
When we affirm "I believe in one God", we go straight to the heart and to what substantiates all aspects of our faith: that is, we believe that God is one only. By making this statement, we take for granted a so-called preambolum fidei, or that there is a prerequisite of the reason to this article of faith. It is the assumption that God exists.
The existence of God precisely speaking, is the goal of man's knowledge, as we have already seen in the first lessons: it is without doubt that God can be known with certainty through human reason. But, this does not mean that all men come to know God with certainty through the light of reason.
In this regard, St. Thomas wondered if was possible to believe by faith what is known by reason, to this end, we refer in particular to the Summa Teologica, secunda secundae, quaestio sei, entitled: "If the truths of faith can be the object of science or knowledge".
“It is impossible that one and the same thing should be believed and seen by the same person. Hence it is equally impossible for one and the same thing to be an object of science and of belief for the same person.”
However, in the answer to the third objection, St. Thomas says:
" Things which can be proved by demonstration are reckoned among the articles of faith, not because they are believed simply by all, but because they are a necessary presupposition to matters of faith, so that those who do not know them by demonstration must know them first of all by faith."
In this sense, the existence of God is a necessary presupposition to adhere to God, to believe that God is one; and thus, whoever does not know it through natural knowledge, can at least know it through the knowledge given by faith.
Still, errors exist that are contrary and diametrically opposed above all to this pre-required knowledge, that is, the knowledge of the existence of God.
What are these errors?
1- ATHEISM OR ANTI-THEISM, which argues that it is possible to rationally deny the existence of God.
2- AGNOSTICISM. Agnosticism is an affirmation that human reason cannot know with certainty that God exists.
3- FIDEIST TRADITIONALISM, affirms that God can only be known by supernatural revelation.
These three errors are to be rejected primarily on the grounds of reason, because we have examined how the existence of God can be known with certainty through natural reason, although not all people obtain this knowledge.
It is equally clear therefore that this first article of faith "Credo in unum Deo", does not simply say: "I believe that God exists", but implies a movement of adherence to God with one’s whole person.
What is meant when we say, "I believe in unum Deum"?
By this expression, we affirm the uniqueness and unity of God.
What is the uniqueness of God?
The uniqueness of God means to understand that there is only one God and there are no other divinities. In a more technical way, we speak of a uniqueness not of species, but of individual substance. If we think of the human being, it is a single species - the human species - but at the same time we cannot affirm that it consists of a single individual substance, because every single human being is made of a different individual substance. In God, on the other hand, there is a single individual substance, precisely the one God. What is the plurality of God? It is that not that of an individual, but of persons. For example, in the Creed of Saint Athanasius it is said that the Father is God, the Son is God and the Holy Spirit is God; yet they are not three gods, but one God. The affirmation of God's uniqueness includes this unity.
What does it mean that God, besides being unique, is one?
Unity could also be called simplicity, in the sense that God is His own nature and therefore is in Himself undivided in a metaphysical sense; there is, in fact, no division in the divine substance, there is no composition, but God is simply in Himself.
When we affirm this article of faith what is excluded? We remove the plurality of divinity which historically takes two forms:
- polytheistic, or the affirmation of several divinities;
- dualistic, that is the school of thought or religion which affirms the existence of two opposing principles at the origin of reality and which both have divine nature.
Take note! Polytheism and dualism must not be opposed by making another mistake: monism.
What is the difference between monism and the oneness of God?
When we speak of the uniqueness of God we speak of it in relation to His individual substance; instead when we speak of monism we are referring to the relationship between God and Creation. For monism, God and creatures actually belong to the same nature or to some extent to the same substance; there is no ontological difference between God and creatures, and this without obviously untrue. Monism should not be opposed to polytheism and dualism, but rather to the concept of metaphysical distinction or creation, by means of that very important philosophical category of "participation".
What does the concept of participation indicate?
That it is true that Creation is not totally disconnected from God, as everything receives being from God; but precisely in this sense it is also distinct from God, who is the Being Himself. Created things receive being from God, who instead is the Being by essence.
IN CONCLUSION. We have examined why this article of faith - "in unum Deum" - already implies adherence to God and for this reason the first commandment is the correlative article of faith. It is essential to understand this relationship: all the commandments have to do with moral life; however, they are not the expression of a moralism closed in on itself, but are the expression of a deeply theological moral life, that is, linked to God and to the expression of our faith. When we speak of the commandments, and in this case of the first commandment, we are not speaking of an attitude to be assumed but of the concrete translation, of mankind's response to God who reveals Himself:
God reveals Himself as the one and only God and mankind responds to God by accepting His first commandment: "You shall have no other God before me".