What does αέναη σοφία mean in Greek?

Yes, I’m going to have fun with this.

First: HAH! You’ve outed yourself as a Modern Greek speaker, Anon OP! In ancient Greek, that would be ἀέναος σοφία. Compound adjectives used the masculine ending for the feminine; and αέναη is what you get when noone you know has been aware of Greek vowel quantity for the past two millennia.

Yes, as Dimitra Triantafyllidou and Konstantinos Konstantinides have said, the adjective means “ever-flowing”, from ἀεί “always” and νάω “to flow”: first attested in Pindar and Herodotus. Used of rivers, lakes, the river Acheron (Are there any Greek towns built along the Acheron river in Greece?); and God bless, Aristophanes had to go and invert it, and use it of bogs and shit (Frogs 146).

Looking at the metaphorical uses of the adjective listed in LSJ. They started early: you have

• glory (Simonides, Heraclitus)
• honour (Pindar)
• power (Euripides)
• tables (Pindar, as a metonymy for hospitality)
• good words (Cratinus)

So use to refer to wisdom sounds entirely plausible. And in fact the phrase ἀέναος σοφία is used by several theologians:

• Philo, On the Posterity of Cain and His Exile §151: she went to the ever-flowing wisdom of God, τὴν ἀένναον τοῦ θεοῦ σοφίαν
• Also: the Epitaph of Pectorius (“ever-flowing waters of enriching wisdom”, Ὕδασιν ἀενάοις πλουτοδότου σοφίης); Diadochus “ever-flowing and completely true wisdom”; Macarius and Anastasius of Sinai “ever-flowing spring of wisdom”; Ecumenical Council of Ephesus “the seas of the ever-flowing knowledge and wisdom of Christ”.

So many instances still make the metaphor explicit, between ever-flowing water and perpetual wisdom; but the earliest instance in Philo doesn’t, and the metaphors with other abstractions, such as glory and power, were well established already.

So. We’ve established that ἀέναος σοφία for ever-flowing wisdom is an established expression. Now to Magister Michael Masiello’s query as to whether “ever-flowing” is the right rendering of “perpetual”.

Etymology is “ever-flowing”. The association with rivers and seas and springs is explicit throughout Byzantium. That’s not unchanging eternity, that’s continually renewing perpetuity. So yes, it is perpetual and not eternal.

Ink away. Philo himself wouldn’t approve the tat (Jewish Orthodoxy is funny about body markings); but his Greek does.