Q. Did Moses just write the Torah in Hebrew or did he or someone else translate it into other languages?
One could ask why, if this was the case, the sages of a later generation decreed a fast on the day when the Greek translation – the Septuagint – was made (the story of the translation as narrated in the Letter of Aristeas says that 72 Jewish elders, six from each tribe of Israel, produced the work).
One answer is that the Greek translation was of the entire Torah, not just those parts that have universal application. Further, the motivation was different. Moses wanted the world to acknowledge God, and believed that in order to facilitate this, the nations needed to know God’s Word. Ptolemy Philadelphus (c. 285-247 BCE) of Egypt, who commissioned the Septuagint, was not concerned to spread belief in the Creator but to promote the assimilation of Jews into Hellenistic culture.
The rabbis who ordained the fast were seriously concerned that the Greek translation would supersede the Torah; Moses’ concern was to make the translation an aid to Torah and not its replacement. The rabbis also worried that the Greek translation was not completely accurate and could mislead people, in the same way in which in our day people often limit themselves to the English translation and miss the nuances of the Hebrew original. Very often we see the truth of the Italian saying, “A translator is a traitor”.