genative and accusative in John 17:5

Greek Learning Greek
1

Hi,
I am sort of beginning-to-intermediate in my Greek. I’m studying Mounce’s Basics of Biblical Greek. Also have Wallace’s Greek Grammar Beyond the Basics. I co-taught 2 quarters of Greek at my church last year, but it was very, very basic stuff. A half-dozen survivors of that class (myself included) are beginning a one-hour per week (plus blog) Greek study group, using Mounce (BBG) because we all want to get really grounded from square one.

My question:
(pardon my attempt at betacode) …

Near the end of John 17:5 is this phrase, “pro tou ton kosmon einai”, which I see translated in NASB as “before the world was”. I see the pronoun “pro” which takes genative and is in fact followed by a genitive article, tou. But then “ton kosmon” is accusative. Furthermore, the phrase ends with an infinitive “einai”. Could you please explain what is going on in this phrase?

Thanks in advance for your consideration.
Steve

2

First, this is an “articular infinitive,” that is, a verb infinitive with the definite article τό. Second, the subject of an infinitive is in the accusative, so we have ὁ κόσμος ἐστί “the world is” getting turned into τὸν κόσμον εἶναι. Tack the preposition and article onto it and you get πρὸ τοῦ τὸν κόσμον εἶναι.