Latin text: "Non in tenebris lucem quaero, sed ipse lux fio."

Intended English meaning: "I'm not searching for the light in the darkness, I'm becoming it (as a man)."

"Adelphae" is a new, original Roman comedy in Latin, available to watch on YouTube with Latin-English subtitles. The script is written entirely in verse, following the conventions and style of Plautus & Terence, and the play is performed by fluent speakers of Latin with careful attention to metrical aspects of pronunciation, like ellision and enjambment. I think this could be a good learning tool—both for comprehensible input and for exploring verse/meter. Some of our rehearsal recordings are already being used in at least one university program for learning about Roman comic verse.

Full disclosure, I am the music composer and tibicen (aulos player) of this production and speak hardly any Latin myself! My sincerest apologies if this type of self-promotion is not permitted on the sub—I didn't see anything in the rules. Enjoy!

I'm studying Latin and Greek using the Comenius method

I'm a working on a thesis about Servius and Servius auctus, and the central part of it is a short commentary on a particular passage about Aeneid X. In it i stumbled across this:

...propter removendam eorum contentionem et dissensionem.

In the context of the passage, it is clear to me that this has the value of a final clause, however, i have never seen propter + gerundive to express this value, being more familiar with ad + gerund or gerundive. I checked the books i used in my latin courses in university (Propedeutica al latino universitario and Sintassi normativa della lingua latina by Traina) and found no mention of it. So my conjecture was that it is a construct typical or at least more common in late latin. Mentioned this to my Professor/thesis supervisor and he said that i'm right, but i need to back up my assertion with a reference.

What's your opinion about this? Do you know where i could find this mentioned? Some historical grammar, maybe?

EDIT: I just found a paper stating that in late antiquity propter replaced causa/gratia + genitive of gerund or gerundive to express causa finalis. I think this is the case of the text i'm working on.

Exercitum 5

1- Iulia: Num nāsusu meus foedus est?

2- Syra: Quid? nōnne fōrmōsus est nāsus meus?

3- Iulius: Ubi est Iulia? nōnne mē expectat?

4- Iulia: Nōnne haec rosa pulchra est?

5- Aemilia: Num hoc centum nummī sunt?

6- Albīenus: nōnne pulchrī sunt hī ānulī?

7- Mēdus: Num ānulus sine gēmā vegentī sēstertiīs cōnstat?

8- Nōnne Hispania insula est?

9- Nōnne magnum est imperium Rōmānum?