About the Mystery of the Letters the mid-6th century, in which Mar Saba had played an important role. The anonymous author of the treatise declares he was prompted to the study of the secret meanings of the letters by the words of the Apocalypse, "I am the Alpha and Omega", and that he subsequently received a vision about them on Mount Sinai. The author proposes a re-modelled Greek alphabet reduced to 22 letters on the model of the 22 letters of Hebrew (discounting Xi Ξ and Psi Ψ), and with the Hebrew letter names. He then interprets these letters as symbolic figures of 22 works of
Alphabet rise to the Hebrew script. The South Arabian alphabet, a sister script to the Phoenician alphabet, is the script from which the Ge'ez alphabet (an abugida) is descended. Vowelless alphabets, which are not true alphabets, are called abjads, currently exemplified in scripts including Arabic, Hebrew, and Syriac. The omission of vowels was not always a satisfactory solution and some "weak" consonants are sometimes used to indicate the vowel quality of a syllable (matres lectionis). These letters have a dual function since they are also used as pure consonants. The Proto-Sinaitic or Proto-Canaanite script and the Ugaritic script were the first