The question of whether Hebrew has vowels is a tricky one because it requires a distinction between spoken and written language. All spoken languages are composed of sounds generated in part by breathing, and linguists designate unrestricted air flowing over the vocal tract resulting in audible sounds as vowels. Thus, all spoken languages have vowels. But vowels weren’t always represented in ancient writing.
So the question is: Did Hebrew have vowels in its written alphabet?
In its earliest phases, around the 10th century B.C.E., there weren’t any vowels in the Hebrew abjad (the word for consonantal alphabets that begin with the equivalent letters a, b, g, and d). Only 22 consonants were used to make up words. However, as more people learned Hebrew and its grammar became more sophisticated, some of these letters began to serve a dual purpose as vowel letters. Specifically, these letters—the waw (ו), yod (י), aleph (א), and later the heh (ה)—were sometimes used as matres lectionis, Latin for “mothers of reading,” to help readers pronounce some words that were commonly mispronounced or misunderstood.
Matres lectionis began appearing infrequently in Hebrew inscriptions in roughly the eighth century B.C.E. and became more common over the centuries. In fact, a general rule of thumb in Hebrew texts is the more “plene vowels” (or vowel letters) that appear in a Hebrew text, the later the text is.
The Jewish historian Josephus references vowels in War of the Jews (5.235). He states that the Jewish high priest wore a golden crown that was engraved with the holy name [of God], composed of “four vowel letters” (φωνήɛντα γράμματα τέσσαρα). Interestingly, this is the only time Josephus uses the Greek word φωνήɛντα (“vowel”) in any of his writings. Furthermore, he doesn’t elaborate on the fact that Yahweh’s name is made up of these vowel letters. But, as a skilled writer of the Greek language, and as a Jew with a knowledge of Hebrew, he is obviously aware of the difference between what first Plato and later the second-century B.C.E. Greek grammarian Dionysius Thrax described in his work, Ars Grammatica, as the phōnēenta (Greek: φωνήɛντα), or “sounding” Greek letters—by which he meant the breathed vowels α, ɛ, η, ɩ, ο, υ, and ω—and the áphōna (Greek: ἂφωνα), or “unsounding” Greek letters—by which he meant the remainder of all the breathless consonants.
This means that Josephus preserved in his writing what all readers of Hebrew knew at the time: There were some letters in the Hebrew alphabet that had developed a secondary usage as vowel letters. But unlike Greek, which had separate letters to represent these breathed vowels, Hebrew readers would simply have to know from experience and education when these dual-purpose letters were vowels and when they were consonants. It was not until the 11th century C.E. that scribes called the Masoretes formally codified the pronunciation of the text of the Hebrew Bible by adding the vowels we see today above and below the text.—B.C.