Credo in unum Deum
“I believe in one God.”
Nicene Creed (Latin liturgy)
What does “Credo in unum Deum” mean?
Credo in unum Deum translates as “I believe in one God.”
The opening words of the Christian creed: a declaration of faith in a single God. People also use it more broadly for a statement of what they hold most firmly.
“Credo in unum Deum” word by word
| Latin | English | Grammar |
|---|---|---|
| Credo | I believe | first person singular present indicative active of credo, “to believe, to trust”; takes in with the accusative to mean “believe in” |
| in | in | preposition; here followed by the accusative (in + accusative), expressing the object of belief |
| unum | one | accusative singular masculine of unus, “one”; agrees with Deum |
| Deum | God | accusative singular masculine of deus, “god”; the object of in |
How to pronounce “Credo in unum Deum”
The two systems sound almost the same here. In church Latin the short i of in is often a little closer to “een”. Stress the first syllable of credo and unum, and the first syllable of Deum.
The story behind it
Word for word the line says “I believe in one God”. In Latin the verb comes first, so credo opens the sentence, and the whole creed continues in this first person: “I believe in one God, the Father almighty”.
These are the opening words of the Nicene Creed in its Latin form. The creed goes back to the Council of Nicaea in 325 and was reworked at Constantinople in 381. It was originally written in Greek, with the Latin text of the liturgy translating it.
The words are sung or spoken at Mass, and composers have set the Credo to music for centuries, from Gregorian chant to Bach’s Mass in B minor and Mozart’s masses. Outside church the phrase is also used for a personal statement of conviction.
How to use “Credo in unum Deum”
A natural choice for a baptism or confirmation gift, a church music programme, or a piece of art or a tattoo about faith. Because it is so closely tied to the Christian creed, it fits best where that religious meaning is wanted.
- Latin
- Credo in unum Deum
- English
- I believe in one God.
- Source
- Nicene Creed (Latin liturgy)
- Era
- Late Antiquity
- Theme
- Faith
Common mistakes
- Credo does not mean “credo” in the English sense of a set of beliefs. In Latin it is the verb “I believe”.
- Credo in unum Deum means “in one God”. Leaving out in or changing Deum to Deus breaks the grammar, because in takes the accusative here.
- Credo alone (“I believe”) is not the same as Credo in unum Deum. Do not treat shortened forms as equivalent.
- In the full creed the line continues with Patrem omnipotentem (“the Father almighty”), so it is a clause in a longer sentence, not a complete motto on its own.
Questions about “Credo in unum Deum”
What does “Credo in unum Deum” mean literally?
“I believe in one God.” Credo is “I believe”, in is “in”, unum is “one” and Deum is “God”, all in the accusative after in.
Where does “Credo in unum Deum” come from?
It opens the Latin text of the Nicene Creed, which goes back to the councils of Nicaea (325) and Constantinople (381).
How do you pronounce “Credo in unum Deum”?
In classical Latin: KREH-doh in OO-noom DEH-oom. Church Latin sounds nearly the same, with a slightly closer i in in.
Is “Credo in unum Deum” correct Latin for a tattoo?
Yes. It is grammatically correct and well established. It is a Christian statement of faith, so be sure that meaning is the one you want.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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