Do we ever see "in saeculo saeculorum"?

Question

Recently, luchonacho asked about the phrase in saecula saeculōrum: literally, "into the lifetimes of the lifetimes". It's kind of a weird phrase, for multiple reasons.

However, I'd always thought the phrase was in saeculō saeculōrum: using singular instead of plural, and ablative instead of accusative. With singular, it's a common Hebraism (as in "the holy of holies", "the king of kings", "the song of songs"), and with the ablative, it means "in" (as in, "during") instead of "into".

It seems I may have fallen prey to the Mandela Effect, as I can't find that particular phrasing anywhere. Did I just make it up? Or does the version with ablative singular actually exist somewhere?

Answer 1

No, this only occurs as "in saecula saeculorum" or "in saeculum saeculi."

The proximate reason is that Jerome is literally translating the Greek terms:

εἰς τοὺς αἰῶνας τῶν αἰώνων (e.g. Gal 1:5)

or:

εἰς τὸν αἰῶνα τοῦ αἰῶνος (e.g. Heb 1:8)

The equivalent Hebrew expression in the Psalms (e.g. Ps 132:14) was already translated in the Septuagint as "εἰς αἰῶνα αἰῶνος."

Greek εἰς + acc. is literally much closer to Latin in + acc.; ἐν + dat., on the other hand, would be translated with in + abl.