Why Did Koiné Greek Still Write Double Letters?

Question

Languages develop double consonants and other quirks for different reasons -- English' double consonants were originally developed because the consonants were doubled in speech, like Latin, and that later developed to how early modern, modern, and contemporary English all used double consonants to show that the proceeding vowel was a short vowel. In Spanish, the letter ⟨n⟩ was doubled to show that the consonant used was pronounced /ɲ/, and Korean uses double letters to show that consonant with voiced aspiration is used. Over time, pronunciation of these changes, and due to this, they are still used with new pronunciation.

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My Case And Argument As To Why I Ask:

One thing I notice is that even going back 1900 years, to my understanding, the letter Veeta ⟨β⟩ was most likely pronounced as either or both of /v/ or /β/, and I see that, for instance, the Hebrew word רַבִּי pronounced as /rabi/ was transliterated as ῥαββί. I would think that this alone would imply that it could have been that ⟨ββ⟩ was a digraph for the sound /b/ but ⟨β⟩ on its own would have been either /β~v/, thus rendering the word as being pronounced as probably /r̊abi~rabi/. This is probably a weak argument to turn to, but ⟨γ⟩ when in digraphs, the first becomes /ŋ/. But I think that a stronger argument is is that the letter Veeta is from the Phonecian letter beth, which was pronounced as both /b/ and /β/, and it was adopted into Hebrew performing these two functions which then became /b/ and /v/ (perhaps as it did into modern Greek, but /b/ was dropped.)

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I have digressed, but I pray this shows better why I ask this question.

Either way, linguistics, especially historical linguistics, it can be hard to be certain of anything, especially if lacking in complex descriptions or especially recordings.

Answer 1

Your speculation is more or less right, not a weak argument at all.

In a word like רַבִּי ~ ῥαββί ~ rabbi we can see the influence of Hebrew/Aramaic. The dot you see in the beth is, as you probably already know, a dagesh. The dagesh in Hebrew indicates various pronunciations whose common feature is that they involve a "stronger" version of a sound. For example, a beth without a dagesh was pronounced as the fricative /β/ whereas one with a dagesh was pronounced as the stop /b/.

The underlying phonological processes for this were various. One of them is simply forte/lene positions, e.g. postconsonantal vs. postvocalic. Another is duplication. Semitic languages have a root system where words usually consist of three consonants, and one of the "defective" root types is roots where two consecutive consonants are the same. They are defective because in speech those two consonants tended to merge into one long consonant, which was also represented in writing. That long consonant, even if originally a weak version of the phoneme, would then become a strong version. For example, /β:/ would be /b/ (I can't remember right now if that would be /b/ or /b:/). As one of the indicators of the root, this pronunciation carried semantic value.

The caveat is that the dagesh was invented long after the time of both Hebrew and Koine Greek. Thus, in the Hebrew writing system of the time, strong/weak pronunciations of certain letters were not marked. Problematically, a casual reader of that word with a cursory knowledge of Hebrew would probably conclude that it was weak because of its postvocalic position. My speculation is therefore that the Koine Greek spelling you identify is an attempt to represent that difference. We can see in the modern writing system that רַבִּי has a strong beth, but they could only hear it, not see it. So the transliterators into Koine Greek opted to helpfully mark it.