The MT text reads thus:
וַיֹּאמֶר שָׁאוּל אֶל יְהוָה אֱלֹהֵי יִשְׂרָאֵל הָבָה תָמִים וַיִּלָּכֵד יוֹנָתָן וְשָׁאוּל וְהָעָם יָצָאוּ.
Therefore Saul said unto the LORD God of Israel, Give a perfect lot. And Saul and Jonathan were taken: but the people escaped. (KJV)
The LXX however reads very differently. It is generally accepted that it reads thus:
Then Saul prayed to the LORD, the God of Israel, “Why have you not answered your servant today? If the fault is in me or my son Jonathan, respond with Urim, but if the men of Israel are at fault, respond with Thummim.” Jonathan and Saul were taken by lot, and the men were cleared. (NIV)
S. Driver reconstructs the text thus:
אם יש בי או ביהונתן בני העון הזה... הבה אורים, ואם ישנו בעמך ישראל הבה תֻּּמִים
This is a very radical reading of the text, and most scholars believe that it ultimately proves that the Urim and Thumim were a form of lot casting (similar to flipping a coin).
However the NETS has a very different translation:
If this guilt is in me or my son Ionathan, O Lord God of Israel, give clear ones, and if this is what you say "In your people Israel", give now holiness
What is the reason for this change in the NETS? I cannot read Koine Greek so I would appreicate help from anyone familiar with the LXX's language. I know that the words Urim and Thumim are rendered in at least 3 different ways in the LXX, so that may be the reason for the different translations. But my question is, are the terms translated as Urim and Thumim in the LXX here, also used for Urim and Thumim elswhere in the OT, or are these terms not at all related to Urim and Thumim elsewhere? If they aren't related elsewhere, then I would be suspicious of Driver's translation of the Greek.