The name of YHWH was also invoked during the daily recitation of the priestly benediction described in Numbers 6:22-27. When the priests pronounced this blessing, "in the Temple they pronounced the Name as it was written, but in the provinces by a substituted word [ha-šēm or ădōnāy]." The Talmud, a 4th to 6th century A.D. commentary on the Mishnah, describes this practice:

R. Tarfon said: "I once ascended the dais [of the temple] . . . and inclined my ear to the High Priest, and heard him swallowing [i.e., whispering or pronouncing indistinctly] the Name [YHWH] during the chanting by his brother priests." (Babylonian Talmud, Kiddushim 71a.)

If this report is accurate, it means that the name may have been whispered so that only nearby priests could hear it distinctly, but not the people receiving the blessing, thus not revealing the sacred name to the non-priests. When the temple was destroyed and the ritual pronunciation of the name ceased, priestly and rabbinic scholars preserved the correct pronunciation for several centuries by whispering the name to their disciples once every seven years, but eventually the correct pronunciation of the sacred name was lost.

The rabbis similarly creatively misread Exodus 3:15 as authorization for this practice. The text says that YHWH is to be God's name "forever," in Hebrew lĕ-ʿōlām. The unvoweled Hebrew word is L-ʿLM, which can voweled and read as as lĕ-'allēm (Lĕ-ʿaLLēM instead of Lĕ-ʿōLāM), which renders the meaning "concealed." Thus, they took this passage as a command to conceal rather than pronounce the divine name revealed by God to Moses. This is part of the rabbinic tradition of God's hidden, unpronounceable, and "ineffable name," the šēm ha-mĕfôrāš.

This phrase is not found explicitly in the Hebrew Bible, but derives from an Aramaic Targum interpretation of Judges 13:18, where an angel asks, in Hebrew, "Why do you ask my name, seeing it is wonderful (pelīʾy)?" The Aramaic Targum of Judges translates "wonderful" as mĕpāraš "ineffable," meaning that the name of God is unpronounceable or unknowable. By the era of Jesus there was thus a strong tradition of the sacred secrecy of God's name, which could only be revealed in the temple by the High Priest on the Day of Atonement or in temple blessings.

For a complete version with notes, see DropBox
http://dl.dropbox.com/u/15865520/Enigmatic%20Mirror/EM-John%208d.pdf

Or Academia.edu:
http://byu.academia.edu/WilliamHamblin/Papers/699242/_Before_Abraham_was_I_AM_John_8_48-59

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