In aeternum
“For ever.”
Latin liturgical expression
What does “In aeternum” mean?
In aeternum translates as “For ever.”
It means forever, without end. It expresses lasting love, faith or commitment.
“In aeternum” word by word
| Latin | English | Grammar |
|---|---|---|
| In | into, for | a preposition (governs the accusative here); with a noun of time it gives the sense “for” |
| aeternum | eternity, ever | accusative singular neuter of aeternum, “eternity” (from the adjective aeternus, “eternal”), used as a noun after in |
How to pronounce “In aeternum”
The main difference is the diphthong ae, which is “eye” in Classical Latin and “eh” in Church Latin. In both, the stress falls on the second syllable of aeternum.
The story behind it
Word for word the phrase says “into eternity”, which in English becomes “for ever”. Latin often uses in with the accusative to mean “for” a period of time, and here that period has no end.
The phrase belongs to the Latin of the Church, not to classical authors. It appears often in the Vulgate Psalms and in prayers, where God’s mercy, name or word is said to last in aeternum.
It is the same wording as the better-known “in saecula saeculorum” (“for ever and ever”) in many liturgical texts. Today it is mostly chosen for inscriptions about love, faith or remembrance.
How to use “In aeternum”
Well suited to a wedding ring engraving, an anniversary gift, a memorial stone or a tattoo about lasting love or loyalty. It also works as a short, solemn closing line on a card or dedication.
- Latin
- In aeternum
- English
- For ever.
- Source
- Latin liturgical expression
- Era
- Church Latin
- Theme
- Love
Common mistakes
- Writing it as one word (“inaeternum”) or with the spelling “eternum”. The standard form is two words, with ae in aeternum.
- Using it where you mean “for life”. In aeternum means without end, beyond a lifetime, which is a stronger claim.
- Treating it as a classical Roman saying. It is mainly Church Latin, shaped by the Vulgate and the liturgy.
- Expecting it to change for gender or number. Here aeternum is a fixed noun, so the phrase stays the same for any speaker or subject.
Questions about “In aeternum”
What does “In aeternum” mean literally?
Literally “into eternity”. It is normally translated as “for ever” or “for all time”.
Is “In aeternum” correct Latin for a tattoo or ring?
Yes. It is a genuine Latin phrase, used for centuries in the Vulgate and the liturgy. The spelling is in aeternum, two words.
Where does “In aeternum” come from?
It is a common expression in Church Latin, found many times in the Vulgate Psalms and in liturgical prayers. It has no single author.
How do you pronounce “In aeternum”?
Classical: “in eye-TEHR-noom”. Church Latin: “in eh-TEHR-noom”. The stress is on the second syllable of aeternum in both.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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