For a little over a year and a half (26 June 2018 to 4 February 2020), I followed along in the Daily Dose of Greek videos on Revelation (copying out each verse). This is where I learned that the Greek phrase "τοὺς αἰῶνας τῶν αἰώνων" literally means something like "the ages of the ages" but is an idiom that means "forever." (The first instance of this that I could find is in Revelation 11:15.)
As I noted before, since the lectionary started over in December, I've been following along with each Sunday's readings in French. I have a French New Testament and a French hymnal that has most of the Psalms. At end of the Gloria Patri after each Psalm, the French has "les siècles des siècles," and for a few weeks, I'd been suspicious that this is the same way that the French New Testament translates "τοὺς αἰῶνας τῶν αἰώνων." I finally lookt it up a couple weeks ago, and not only did I confirm that, but I also discovered that "les siècles des siècles" has the same literal meaning as "τοὺς αἰῶνας τῶν αἰώνων" - "the centuries of the centuries."
