Rabbi J. H. Hertz, in his commentary on the Torah (second edition, p. 405) lists some basic differences between Hammurabi's civilization and laws on the one hand and the Torah's on the other. Perhaps most important is that there are no Babylonian loan-words in the Torah. The legal section has no Babylonian terminology at all. This alone is a key indicator that it is not based on Babylonian laws because, as a general rule, a higher culture forces its language on a primitive people that adopts its culture. If the Torah's laws were based on Hammurabi's, one would expect some of is legal terminology to be adopted as well.

Also, it cannot be minimized that the Babylonian and Jewish societies were extremely different. The Babylonians were industrialized and urbanized; they lived in cities and conducted international commerce. The Jews, however, were nomadic, rural, and primitive. Were they to adopt the laws of a culture that was so different, the laws would have no relevance to their daily lives.

The other differences that Rabbi Hertz lists can be analyzed further to uncover their underlying themes. By doing this, we can understand more than just the details of the laws. We can understand the reasons for the laws. This, Professor Moshe Greenberg has shown, demonstrates the stark differences between these legal codes (Yehezkel Kaufman Jubilee Volume, pp. 5-28). The following is based on Professor Greenberg's analysis.
The main difference between the two law systems can be found in the introductions and side comments of the codes. Hammurabi repeatedly refers to his code as "my words which I have inscribed on my monument." They are his words. In the Babylonian theology, the king was appointed by the gods to establish justice. The king was the source of the law.

In the Bible, this is not the case. G-d is the source of the laws. They are referred to as "words of G-d" and never of man. Indeed, violation of the law is seen as a religious sin. "He who acts wilfully [against the law] whether he belongs to the native-born