Origen, a Christian writer of the second and third centuries C.E., stated that, in the more correct copies of the Greek translations of the Hebrew Scriptures, the Tetragrammaton, or sacred name of Jehovah, was written in ancient Hebrew letters.
... Fragments from the late fifth or early sixth century C.E. of Aquila’s Greek version also contain the divine name written in ancient Hebrew characters.—NW appendix, p. 1563, Nos. 7, 8.