I've heard (not sure if accurate), that when reading aloud in Latin,
the Romans read syllable by syllable, not word for word or phrase for phrase. If true, they might not have felt the need for punctuation as much. I expect the felt need for punctuation developed as book production of Latin classics increased in the Middle Ages or Renaissance. Certainly it would have after the invention of printing.
Solo denarii duo mei,
Devenius
Which raises the question: when the Romans
spoke, did they also
speak syllable by syllable, and not word for word?
And what does reading or speaking syllable by syllable actually mean? That they paused between one syllable and the next (instead of between one word and the next), like a first-grader who has some difficulty with the reading, or that it was one continuous flow of syllables (with pause maybe only between phrases -- er, actually you're saying there was no pause there either, I guess)? Continuous flow is more the way we speak, if we're fluent in our language. At least that's my experience in the modern world.
So far as I know, punctuation in Latin (which has evolved over the centuries) began with Irish scribes, who are also credited with introducing spaces between words. I have heard that this developed in Ireland, because Ireland had no tradition of spoken Latin in the classical period nor thereafter, therefore Latin for them was very much a written language which got into their heads via the eyes rather than the ears. This being the case, they looked for ways of making the individual words, clauses and sentences easier to recognise.
Yay, Irish scribes!
My copy of the Vulgate does not have punctuation (or if any, it is very rare, except for hyphens), but it does separate the words. It is usually not difficult to figure out because the lines break at appropriate places, e.g.,
In principio creavit Deus caelum et terram
terra autem erat inanis et vacua
et tenebrae super faciem abyssi
et spiritus Dei ferabatur super aquas
dixitque Deus
fiat lux et facta est lux (Genesis 1:1-3)
The
ets and
-ques also help (as Ybytyruna has noted -- the particles).
Nevertheless, sometimes punctuation would make the structure and meaning clearer. I think I'd have considerable trouble without punctuation if I were reading, say, Cicero.
But if the punctuation is not in the original text, then there's sometimes a risk that the sentence(s) should have been punctuated otherwise than what the editor thought and did.