Origen's textual studies on the Old Testament were undertaken partly in order to improve the manuscript tradition, and partly for apologetic reasons, to clear up the relation between the LXX and the original Hebrew text.
The results of more than twenty years' labour were set forth in his Hexapla and Tetrapla, in which he placed the Hebrew text side by side with the various Greek versions, examined their mutual relations in detail, and tried to find the basis for a more reliable text of the LXX.
Now that the ascription " to David " was understood of David's authorship before the time of the LXX.
Moreover the scruple as to the pronunciation of the Tetragrammaton seems to have arisen earlier, as in the LXX.
The translation was executed entirely from the Hebrew, but underwent later revision which brought it more into conformity with the LXX - this to a greater degree in some books than in others.
