"He who shall not be named"
"The ineffable name of God"
Voldemort
or
Yahweh
There's no reason to panic, but Satan worship is real and FAR more common that the average Satanist realizes.
THREE guesses?
Moses asks Hashem when “I come to the children of Israel, and I say to them, 'The God of your fathers has sent me to you,' and they say to me, 'What is His name?' what shall I say to them? (3:13)"
“God said to Moses, I will be what I will be, and He said, ‘So shall you say to the children of Israel, I will be has sent me to you.’”
We pronounce the individual Hebrew letters as a whole name, but say it as yud-kay-vav-kay, changing the letter hay to a kay. In short, we go out of our way not even to get close to what may or may not be God’s name. It is more than a sign of respect; it is a sign of awe.
"And whether or not the name אֶֽהְיֶ֖ה should ever be uttered, I will leave that up to you. The only time that Hashem’s name was fully and correctly articulated was by the Kohen Gadol at Yom Kippur and only in the Holy of Holies. It is called the "Ineffable Name of God"."
https://www.jpost.com/blogs/northern-exposure/the-ineffable-name-of-god-479085
Cabala literally means "oral tradition." An esoteric branch of mystical Judaism, the Cabala is also a school that researches the secret, hidden and meanings of the Torah (or first five Books of Moses) and other Jewish writings. There's more to it, however. A close examination of the Cabala reveals that it actually precedes the Torah. A pagan teaching, it continued to exist after the revelation of the Torah and lived on to spread amongst the followers of Judaism. (For further reading on the subject, see Harun Yahya's Global Freemasonry, Global Publishing, 2002)
For thousands of years, the Cabala has been a resource for sorcery and practitioners of black magic and now enjoys a strong following all around the world, not only in the Jewish community. The Templars were one such group, engaged in research into the Cabala with the goal of acquiring supernatural powers. As the following chapters will examine in detail, they were keen on establishing ongoing relationships with Cabalists in Jerusalem as well as in Europe-a view widely accepted by researchers working on the subject. [14]
14 Alan Butler, Stephen Dafoe, The Templar Continuum, Templar Books, Belleville-Ontario, 1999, p. 70
https://www.bibliotecapleyades.net/sociopolitica/templars/knights_templars01.htm#dipnot
I suppose you're referring to the priests of the pyramid temples. I don't know "who" specifically, but perhaps the scribes of Pharaoh Amenhotep III
Regardless, the "magick" of the proposition of an unspeakable name, remains the same from kingdom to kingdom, carried by the hands that build kingdoms.
Dude was literally talking to a plant…the "burning" bush.
I think it's safe to assume "what" HASHem was.
My final guess would have to be Origen of Alexandria, but though he wrote greatly of "the nature of God", I can't find a connection to him and "the ineffable name of God".