Fourth Lateran Council (1215) – Firmiter Credimus: The Dogmatic Definition on Angels and Demons

The Fourth Ecumenical Council of the Lateran (1215), presided over by Innocent III and the largest medieval council, contains in its first chapter (Firmiter credimus) the fundamental dogmatic definition on the angels and the demons. It is the most important magisterial text on angelology and demonology up to the Second Vatican Council, referenced by all the later catechisms.

Full Latin text – ch. 1 (Firmiter)

We firmly believe and simply confess that there is one only true God, eternal, immense and unchangeable, incomprehensible, omnipotent and ineffable, Father and Son and Holy Spirit: three persons, but one wholly simple essence, substance, or nature. […]

One principle of all things: the creator of all things invisible and visible, spiritual and corporeal; who by His omnipotent power from the beginning of time created at once out of nothing both creatures, the spiritual and the corporeal, that is, the angelic and the mundane; and afterwards the human, constituted as it were in common of spirit and body.

Diabolus enim et alii daemones a Deo quidem natura creati sunt boni, sed ipsi per se facti sunt mali. Homo vero diaboli suggestione peccavit.

Full English translation

We firmly believe and simply confess that there is one only true God, eternal, immense and unchangeable, incomprehensible, omnipotent and ineffable, Father and Son and Holy Spirit: three persons truly, but one absolutely simple essence, substance, or nature: […]

Sole principle of the universe: creator of all things visible and invisible, spiritual and corporeal: who by His omnipotent power, from the beginning of time, created at once out of nothing the one and the other creature, the spiritual and the corporeal, that is, the angelic and the mundane, and afterwards the human, as a common creature constituted of spirit and body.

The Devil and the other demons were indeed created by God naturally good, but they themselves by themselves became evil. Man, however, sinned at the suggestion of the devil.

The Five Dogmatic Affirmations

In the chapter Firmiter, Lateran IV defines five fundamental truths about spiritual beings:

1. Existence of the angels: God created purely spiritual beings (the “angelic creature”), against Gnostic materialism
2. Creation in time: the angels were created in time, “from the beginning of time”; they are not co-eternal with God
3. Original goodness: “they were created by God naturally good” (a Deo natura creati sunt boni), against Manichaean dualism
4. Freedom of the angels: the fall was not by necessity of nature but by free choice, “ipsi per se facti sunt mali” (they themselves by themselves became evil)
5. Action of the devil in the human fall: “man sinned at the suggestion of the devil” (homo vero diaboli suggestione peccavit), cf. Genesis 3

Significance for Theology

Lateran IV dogmatically settles the questions that divided the medieval theologians:

• Against the Cathars and the Albigensians: who affirmed an absolute dualism, two eternal principles, one good (God) and one evil (the Devil). The Council defines that there is only one creating principle, and that even the Devil was created good.
• Against the Gnostics: who denied the creation of the material world by God. The Council affirms that God created all things, spiritual and corporeal.
• Against any determinism: which would deny the freedom of spiritual beings. The Council affirms that the demons chose evil.

Magisterial Legacy

The text “Firmiter credimus” of Lateran IV was cited in full by:

• Council of Florence (1442): Bull Cantate Domino
• Council of Trent: Session III, Profession of Faith
• Roman Catechism of Saint Pius V (1566): see the post on the Roman Catechism
• Vatican I (1870): Constitution Dei Filius ch. 1
• Vatican II: Lumen Gentium nn. 49-50 (the saints in heaven)
• Catechism of the Catholic Church (1992): nn. 327-336 (angels) and 391-395 (fall of the angels)

Pastoral Implications

1. The existence of the angels is a defined dogma, not a free opinion
2. The demons exist as personal beings, not merely as “forces of evil”
3. The fall of the demons was free, irreversible, and definitive
4. The human being can be tempted by the Devil, but is not forced to sin
5. Every demonic temptation can be overcome by the grace of Christ

Further reading

Catechism of the Catholic Church | Roman Catechism 1566 | Lumen Gentium

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See also: What Is Angelology? The Angels in the Bible and in the Magisterium

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