Quoting Jess, as she explains that it's even more complex than I first thought...
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þā … þā does mean "when… then"
but it's not what you see in the "the more the merrier."
That word is actually þȳ, the instrumentive case of "that" (þæt), implying utility or causing something to happen. (more people = merrier times)
<<<
þā is a precursor for 'the.'
þȳ is ALSO a precursor for 'the.'
Both words ended up as 'the' in modern English, and apparently NEITHER ONE is the definite article.
I'm still trying to sort this out. I'm not the expert here, but
*sunglasses*
the more I listen to experts, the smarter I get.
*guitar riff*
*explosion of more and merry*
@my @howardtayler I would be surprised if that were the case. It is not an if/then in German:
"10Dein Reich soll kommen.
Dein Wille soll geschehen.
Wie er im Himmel geschieht,
so soll er auch auf der Erde Wirklichkeit werden."
https://www.die-bibel.de/bibeln/online-bibeln/lesen/BB/MAT.6/Matth%C3%A4us-6
"Dein" is "thy" in English, the familiar form of "your".
@my @howardtayler https://twitter.com/J_mugs/status/1591810244040179713
the highlighted footnote isn't even on the right line (line 9) and (allegedly, I'm less certain about this) says there is a text with the additional words at that point in the text.
@trelane @howardtayler
This was the source where I picked it up - https://twitter.com/ra6bit/status/1591682370171998211 Entirely possible I misinterpreted it as well