Did Moses write the entire "Torah" like Christians claim?

Some sections of the Torah do explicitly say they were written by Moses (e.g., Deuteronomy 31:22: "Moses therefore wrote this song the same day, and taught it the children of Israel"). That might be taken as odd, if he wrote the whole thing.

Also, the entire story of Moses is narrated from third-person omniscient perspective, treating him just like the rest of the characters. That too suggests that Moses was not the author. Take for example the verse: Now the man Moses was very meek, above all the men which were upon the face of the earth (Numbers 12:3). (Also, by definition, if he was the meekest man in the world, he wouldn't have written that – he would have been too modest.) And then Moses died

The rabbis of the Talmudic era did believe that, divinely inspired, Moses wrote the Torah himself - up to the last eight verses. The Talmud preserves a rabbinical dispute about whether Moses wrote those last verses describing Moses death, burial and legacy - or whether they were written by his successor, Joshua (tractate Bava Batra, 14b-15a).

Come the Middle Ages, the rabbis noticed more difficulties. Rabbi Abraham Ibn Ezra wrote in his 12th-century Bible commentary that 12 verses in the Torah are anachronistic and seem to indicate that they were written after the time of Moses. For example, when Moses was alive, the Canaanites still controlled the Holy Land. So the verse ending with And the Canaanite was then in the land (Genesis 12:6) ostensibly could not have been written by Moses, but by someone who lived after the Israelites took over Canaan, that is, after Moses died.

In his commentary on this verse, Ibn Ezra wrote, It holds a secret of which the wise man should be silent (he doesn't tell us what the secret is, but it may be that Moses seems not to have written all of the Torah).

Enter Spinoza

Indeed scholars remained silent on the topic for centuries, until in the 17th century, Baruch Spinoza read Ibn Ezras commentary – and could remain silent no more. In his Theological-Political Treatise (1670), Spinoza elaborated on the topic and concluded that Moses could not possibly have written the entire Pentateuch. His English contemporary Thomas Hobbes came to the same conclusions, without Ibn Ezra's help.

A century later, a French professor of medicine named Jean Astruc set out to prove the two heretics wrong, using the newly- emerging science of textual criticism. With the help of techniques that had, up to then, been applied only to Latin and Greek classics, he studied the Torah and came to the conclusion that Moses compiled the Book of Genesis by putting together two older texts. He published these findings anonymously in 1753.

Using similar techniques, in 1805 Wilhelm Martin Leberecht de Wette, a German Bible scholar, published a study arguing that Deuteronomy had been written by a different author or authors from the rest of the Torah.

Half a century later, in 1853, Hermann Hupfeld, an Oriental studies scholar, showed that what Astruc identified as two sources was apparently three.

All these studies were consolidated towards the end of the 19th century by Julius Wellhausen, another German biblical scholar.