After several years, a Bible verse I thought I knew well just blew my mind. (Well, they sometimes do, but not in the grammatical sense.)
Namely, Mt 16:18 says,
And so I say to you, you are Peter, and upon this rock I will build my church,* and the gates of the netherworld shall not prevail against it.
Clementine Vulgate (as per the Clementine Vulgate project in Sourceforge) says,
Et ego dico tibi, quia tu es Petrus, et super hanc petram ædificabo Ecclesiam meam, et portæ inferi non prævalebunt adversus eam.
Meanwhile, Nova Vulgata, (as per the Holy See) says,
Et ego dico tibi: Tu es Petrus, et super hanc petram aedificabo Ecclesiam meam; et portae inferi non praevalebunt adversum eam.
FWIW, the original Greek says,
κἀγὼ δέ σοι λέγω, ὅτι σὺ εἶ Πέτρος, καὶ ἐπὶ ταύτῃ τῇ πέτρᾳ οἰκοδομήσω μου τὴν ἐκκλησίαν, καὶ πύλαι ᾅδου οὐ κατισχύσουσιν αὐτῆς.
Here, κατισχύσουσιν seems to have the against part implicit in the meaning of the verb.
As I understand, adversus is an adjective, while adversum may also be an adverb. While the latter seems more reasonable (prevail against), I guess the former is also idiomatic. (Is it, even if non-Clasically?).
Is the New Vulgate correcting something that the Vulgate had less correctly conveyed?