What separated Judaism from all other religions?

Answer 1

At the time of Abraham the Hebrew, the area where he lived was full of pagan cults; they were polytheistic, worshiping multiple deities. Abraham was the first to advance the idea of ethical monotheism: the worship of One God, and the appropriate ethical code of conduct.
The Israelites differed from other ancient peoples in the following ways:
1) It was the only religion in which God spoke to the entire assembled nation (Exodus ch.19) of over two million people.

2) It made a complete break from the surrounding idolatry. Their monotheism (belief in One God) set the Jews apart because other ancient nations did not share it. We've heard (for example) of Greek mythology and Roman mythology. What not everyone is aware of is that idolatry tended to go hand in hand with cruel, licentious and excessive behavior, since the caprices which were narrated concerning the pagan gods were adopted as an excuse to imitate those types of behavior.

Compare that to God, who reveals His attributes in the Torah as wise, kind, holy, and pure. God is One, so the command to imitate His attributes (Deuteronomy 8:6) was (and is) a straightforward matter once one is even minimally familiar with the Torah.

(See: What do Jews believe God is like?)

Accordingly, Judaism was:

3) The only ancient religion in which a large percentage of its adherents were literate and scholars.

4) It was the only religion in which the people were ruled by God, with no need for a king, for several centuries (see Judges 8:23 and 1 Samuel 8:4-7).

5) The concept of morality was also the work of the Hebrews' religion, including the dignity and value of a person. It is the responsibility of the community to support the widow, the orphan, the poor, and the stranger passing through.

6) Under the law of Judaism, everyone had recourse to the courts. A child, widow, wife, poor person, etc., could initiate legal action against any citizen to redress perpetrated harm. Compare this to those societies in which only mature, land-owning males had rights.

7) Government is accountable to a higher authority. In other ancient societies, the monarch was all-powerful. Among the Israelites, however, the king was under the constant scrutiny of the Divinely-informed prophets, who didn't hesitate to castigate him publicly for any misstep in the sight of God.

And, other than for the crime of rebellion, the king couldn't punish any citizen by his own decision. He was obligated by the Torah-procedures like everyone else (Talmud, Sanhedrin 19a).

8) A robber repays double to his victim, or works it off. Unlike in many other ancient societies, in Judaism debtors are not imprisoned or harmed. They are made to sell property and/or work to repay what they owe. Compare this to the Roman practice by which anyone could accuse a man of owing them money and the debtor could be killed (Roman Twelve Tables of Law, 3:10).

It is important to note that every one of the above existed in Judaism thousands of years earlier than in other nations. Here's just one example: Infanticide was practiced in classical European nations until Judaism and its daughter-religions put a stop to it.

See also:

Were the Israelites monotheistic?

Israelite culture