Trigrammaton

"A text discovered at Qumrân (4QpapLXXLev) that contains a fragment of the book of Leviticus in Greek (4:26–28) renders the tetragrammaton as Iaṓ: "If anyone transgresses even one of the commandments of Iaṓ and does not follow it ..." (4:27). ... This investigation leads to the conclusion that the ancient pronunciation of the name of the god of Israel was "Yahô", which amounts to saying that the tetragrammaton was originally a trigrammaton. The w in "Yhwh" was not a consonant, but a mater lectionis indicating the sound "o". The letter h at the end of the tetragrammaton Yhwh should be understood as indicating a lengthening of the preceding o."

"The form corresponding to the Greek "Iao" does not occur alone in Hebrew, but only as an element in such proper names as Jesaiah ("Yesha'yahu"), Zedekiah ("Ẓidḳiyahu"), and Jehonathan. According to Delitzsch ("Wo Lag das Paradies?" 1881), this form was the original one, and was expanded into ; but since names of divinities are slow in disappearing, it would be strange if the primitive form had not been retained once in the Bible. ... "Yahu" was in fact used in magic, as is clear from the "Sefer Yeẓirah," which shows many traces of Gnosticism; in the cosmology of this work the permutation of the letters furnishes the instruments of the Creation."