Earnest - Considering it a sacrilege to use some substitute as kyrios ortheos, the scribes inserted the tetragrammaton at its proper place in the Greek version text.
There were obvioulsy several different Septuagint in usage, if I remember correct, and we dont have it today anymore. Perhaps on my next Israel trip I can find a scroll in a tomb.
But this does not change anything in the fact that the Tetragram was not spoken out since the Jews returned from Babylon only by the priests, althought the holy texts were copied with the four letters.
They may have read YHWH in some LXX exemplar but they didnot spell it . They always replaced it by Adonai or other terms. Translating the Lords Name with kyrios was no sacrileg at all, because it was always to see that the NAME OF GOD was meant but simply should not been spelled. There were more conservatice translators and more progressive ones but both are right.
Certainly jesus often quoted from the Septuagint and used Kyrios and did not spell loud the four letters of the Tetragram nor spell the name in hebrew or aramaic, because he would have been stoned for such blasphemy.
Hey everyone who spoke greek if he addressed god said KYRIOS at that time.Therefore the bible was translated into greek and it said Kyrios. Simple they didnt want that people began to spell the holy sacried name as "Yohawuah, or Yehiwei". They wanted to avoid this and that people used it in daily things and said,
"Oh Yehiwei helped me to find my keys again, Oh thank you Yehiwei that my Iphone doesn hangup.", Or "Yehiwehi please please please help to find a girl",
The worst: "Mum, I swear in Yehiwehis name that I learned for the math test."
"Please Yehiwehi dont kill me in Armageddon, and dont let me die without blood"
They didnt like the profan usage of G-Ds name those extrem conversative Jews at Jesus time.
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A fictive story:
One evening Jesus met his apostels and he told them:
"I tell you now the name of God because i want it to proclaim to you,
did you already hear how the highpriest spells the Tetragram in the temple while the other priest are singing so that nobody can hear it, what do you mean, Peter?"
"You dare asking me such a question, you know we are not allowed to spell it, Master".
"You dont understand me yet, i am speaking of something else when I say I proclaim the name to you "
"Proclaiming _ -? -*** doesnt not mean spell out the Tetragram?" asked Peter rethorically.
3"For I proclaim the name of the LORD; Ascribegreatness to our God! 4"The Rock! His work is perfect, For all His ways are just; A God of faithfulness and without injustice, Righteous and upright is He.…