In the Hebrew, the Yod, Hay, Waw, and Hay of the four-lettered Tetragrammaton are pronounced ee-ah-oo-eh. These letters represent vowel-consonants, the only Hebrew letters besides the aleph that can perform as either vowel or consonant. (See “How the Hebrew Language Grew,” by Edward Horowitz.)
Because these letters of Yahweh’s Name serve as both vowels and consonants, we can know which English vowels come closest in sound to the Hebrew letters. Furthermore, the Hebrew Masorete scribes put vowel points in and around the Hebrew letters to preserve their proper pronounciation.
These facts obliterate the argument that we cannot pronounce ancient Hebrew. After all, if we cannot pronounce the Hebrew “because it has no vowels,” then the entire Hebrew Old Testament is unpronounceable. What’s more, the Hebrews themselves would have been unable to pronounce their language!
The ancient Hebrews simply grew accustomed to pronouncing their words with the vowels implicitly supplied. It was not unlike modern teaching techniques in which pupils learn how to read by sight recognition of letter groups rather than phonetically sounding those letters out.