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Unicity of God


The attribute of God by which He is one and unique, and thus set off from the multiplicity of His creatures. This article presents first the scriptural and patristic basis for this attribute and then some theological reflections on the concept of unicity, its attribution to God, and various ways in which it has been negated.

Scriptural and Patristic Basis. The primal truth conveyed by God to His people in primitive revelation is the uniqueness of God, a truth insisted upon as a corrective to the constant human tendency toward multiple deification. At least from the time of Moses on, the patriarchs were all monotheist, and their teaching set Israel apart from its neighbors. "Hear, O Israel the Lord our God is one Lord" (Dt 6.4); "See ye that I alone am and there is no other God besides me" (Dt 32.39). Moses was scandalized at the golden calf, for he saw this as an attempt to give place to another god (Ex 32.31). True enough, the full implications of this revelation were not grasped at once, and for a time the Israelites thought that other gods reigned over the peoples outside Israel. The henotheistic attitude, however, gradually gave way to absolute monotheism as the Prophets, especially Isaiah (Is 4145), gave further clarity to the Word of God.

In the New Testament Christ explicitly repeated the monotheistic formula addressed by Yahweh to Israel (Mk 12.29). Only then did He manifest Himself as distinct in person from Father and Holy Spirit, and even this was done only against the background of understanding an identity of nature: "I and the Father am one" (Jn 10.30); "In the beginning the Word was with God, and the Word was God" (Jn 1.1). St. John and St. Paul give clear confirmation to the truth: " that they may know Thee, the only true God " (Jn 17.3); "one Lord, one faith, one baptism; one God and Father of all " (Eph 4.6).

The understanding of the Fathers as to the uniqueness of God need not be insisted upon; it is evident and unanimous. The magisterium of the Church leaves no room for doubt in the earliest creed, "Credo in unum Deum" (H. Denzinger, Enchiridion symbolorum, ed. A. Schönmetzer [32d ed. Freiburg 1963] 150), and in many conciliar pronouncements, especially those of Lateran IV (ibid. 804806), Florence (ibid. 133637), Trent (ibid.1862), and Vatican I (ibid. 3001).

Concept of Unicity. The concept of unicity, or uniqueness, is but the ultimate and perfect realization of unity. The meaning of unity, in turn, can only be approached negatively as the denial of division and is immediately realized in two distinct orders, viz, the predicamental and the transcendental. Unity in the first sense is mathematical, the principle of number, and is the property of a thing precisely as quantified. Denial of matter and quantity to God renders impossible any attribution to Him of predicamental unity.

Transcendental unity belongs to the metaphysical order and is a property of being as such, really identified therewith. Everything, by the very fact that it is, is actually undivided in itself (whether simple or composed) and divided from all else not itself. Such oneness adds no determination or limitation to being; it is being conceived in its unity. The two notions (being and one) are not, however, equivalent (see transcendentals).

Such oneness is predicated of God, yet in so perfect a way that the unity of God is a unicity. God is so one as to include any other of like nature; He is unique. existence is explanatory of all unity; a purely subsistent existence, one not the existence of an essence, demands unicity (see subsistence).

Attribution to God. The affirmation of God's unicity is possible for unaided natural reason, and the lines of argumentation are varied. The multiplicity and complexity of creatures, though not themselves immediately implying the exclusiveness of God, leads to the recognition of God's simplicity, which is further discernible as a simplicity of infinite perfection. From these two prerogatives of Godsimplicity and omniperfectionHis unicity can be cogently demonstrated.

A plurality within a nature is possible only upon the assumption that the nature admit of composition. The nature, being common, can be differentiated into several individuals only by the addition thereto of distinct singularizing elements. Most obvious of these is the concrete act of existing, which must be entirely unique for each existent. A plurality of gods, then, demands a common divinity that is in a state of composition with other real and distinct principles accounting for its individuation. Granting the absolute simplicity of God, the hypothesis of several gods becomes untenable. (see simplicity of god.)

God's infinity of perfection leads to the same conclusion. The hypothesis of several gods assumes that they differ in some fashion from one another, and such difference can only be in virtue of each possessing or being something that the others are not. Each god would then lack that which distinctly characterizes the others. And such lack is a denial of the divine prerogative of omniperfection; a denial in effect that the being in question is indeed God. (see perfection, ontological.)

Quite simply, the Act of Being in its absolute purity cannot involve any kind of plurality. Existence accounts for the unity of each thing; in God there is nothing besides pure existence; this is God not only One but Unique.

Negations of God's Unicity. Polytheism, acknowledging a plurality of gods, is an implicit negation of God's unity. It represents a primitive stage in the evolution of man's religious attitudes. The empirical investigative sciences, such as anthropology and paleontology, are inclined' to see primitive monotheism as the eventual refinement of an original polytheistic tendency. Catholic thought, on the other hand, relying on the Genesis account of creation, has tended almost entirely to conceive of the origins of polytheism in terms of the corruption of an initial revealed monotheism.

At any rate, the primitive forms of polytheism tend in time to give way to henotheism, i.e., the recognition of a single supreme god for each nation or people. Further refinements give rise to dualistic systems based largely on the polarities of matter and spirit and of evil and good. Historically, these range from the manichaeism of the 3d century down to the teachings proposed by the albigenses of the 13th, and not a little of contemporary pantheism offers a highly sophisticated form of the same ideology.

Finally the revelation that God's nature and life is triune affords, in the very depths of its mysteriousness, occasion for the error of tritheism. Avoidance of this lies in the indispensable understanding that the three Persons do not share a common nature; rather each Person is the divine nature in total identity.

Bibliography: thomas aquinas, Summa theologiae 1a, 11, Eng. tr. and comment. v.2., ed. t. mcdermott (New York 1964), 60 v. planned. john of st. thomas, Cursus theologicus (ed. Solesmes; Paris 1931) 2:101119. r. garrigou-lagrange, God: His Existence and His Nature, tr. b. rose, 2 v. (St. Louis 193436) v.2. e. mangenot et al., Dictionnaire de théologie catholique, ed. a. vacant et al., 15 v. (Paris 190350; Tables Générales 1951)4.1:9481300. c. hartshorne and w. l. reese, eds., Philosophers Speak of God (Chicago 1953).

[w. j. hill]

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