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.
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.)
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.