The Noahide Laws were predated by six laws given to Adam in the Garden of Eden. Later at the Revelation at Sinai the Seven Laws of Noah were regiven to humanity and embedded in the 613 Laws given to the Children of Israel along with the Ten Commandments, which are part of, and not separate from, the 613 mitzvot. These laws are mentioned in the Torah. According to Judaism, the 613 mitzvot or "commandments" given in the written Torah, as well as their reasonings in the oral Torah, were only issued to the Jews and are therefore only binding upon them, having inherited the obligation from their ancestors. At the same time, at Mount Sinai, the Children of Israel (i.e. the Children of Jacob, i.e. the Israelites) were given the obligation to teach other nations the embedded Noahide Laws. It is actually forbidden by the Talmud for non-Jews on whom the Noahide Laws are still binding, to elevate their observance to the Torah's mitzvot as the Jews do.
While some Jewish organizations, such as Chabad have worked to promote the acceptance of Noahide laws, there are no figures for how many actually do. Noahides exist predominantly in the United States, South America and Europe.
The Talmud also states: "Righteous people of all nations have a share in the world to come" (Sanhedrin 105a). Any non-Jew who lives according to these laws is regarded as one of "the righteous among the gentiles". Maimonides writes that this refers to those who have acquired knowledge of God and act in accordance with the Noahide laws out of obedience to Him. According to what scholars consider to be the most accurate texts of the Mishneh Torah, Maimonides continues on to say that anyone who upholds the Noahide laws only because they appear logical is not one of the "righteous among the nations," but rather he is one of the wise among them. The more prolific versions of the Mishneh Torah say of such a person: "..nor is he one of the wise among them.
According to the Biblical narrative, the Deluge covered the whole world killing every surface-dwelling creature except Noah, his wife, his sons and their wives, sea creatures, and the animals taken by Noah on Noah's Ark. After the flood, God sealed a covenant with Noah with the following admonitions ():
The Talmud states that the instruction to not eat "flesh with the life" was given to Noah, and that Adam and Eve had already received six other commandments. Adam and Eve were not enjoined from eating from a living animal since they were forbidden to eat any animal. The remaining six are exegetically derived from a seemingly superfluous sentence in .
One rabbinic opinion holds that not only are non-Jews not obligated to adhere to all the laws of the Torah, but they are actually forbidden to observe them. Rabbinic Judaism and its modern-day descendants discourage proselytization. The Noahide Laws are regarded as the way through which non-Jews can have a direct and meaningful relationship with God or at least comply with the minimal requisites of civilization and of divine law.
A non-Jew who keeps the Noahide Laws in all their details is said to attain the same spiritual and moral level as Israel's own Kohen Gadol (high priest). Maimonides states in his work Mishneh Torah that a non-Jew who is precise in the observance of these Seven Noahide commandments is considered to be a Righteous Gentile and has earned a place in the world to come. This follows a similar statement in the Talmud. However, according to Maimonides, a gentile is considered righteous only if a person follows the Noahide laws specifically because he or she considers them to be of divine origin (through the Torah) and not if they are merely considered to be intellectually compelling or good rules for living.
Noahide law differs radically from the Roman law for gentiles (Jus Gentium), if only because the latter was an enforceable judicial policy. Rabbinic Judaism has never adjudicated any cases under Noahide law (per Novak, 1983:28ff.), although scholars disagree about whether the Noahide law is a functional part of Halakha ("Jewish law") (cf. Bleich).
In recent years, the term "Noahide" has come to refer to non-Jews who strive to live in accord with the seven Noahide Laws; the terms "observant Noahide" or "Torah-centered Noahides" would be more precise but are infrequently used. The rainbow, referring to the Noahide or First Covenant (Genesis 9), is the symbol of many organized Noahide groups, following . A non-Jewish person of any ethnicity or religion is referred to as a bat ("daughter") or ben ("son") of Noah, but most organizations that call themselves בני נח (b'nei noach) are composed of gentiles who are keeping the Noahide Laws.
Some modern scholars however dispute the connection between Acts 15 and Noahide Law.
The tenth century Rabbi Saadia Gaon added tithes and levirate marriage. The eleventh century Rav Nissim Gaon included "listening to God's Voice", "knowing God" and "serving God" besides going on to say that all religious acts which can be understood through human reasoning are obligatory upon Jew and Gentile alike. The fourteenth century Rabbi Nissim ben Reuben Gerondi added the commandment of charity.
The sixteenth century work Asarah Maamarot by Rabbi Menahem Azariah of Fano (Rema mi-Fano) enumerates thirty commandments, listing the latter twenty-three as extensions of the original seven. Another commentator, Rabbi Zvi Hirsch Chajes (Kol Hidushei Maharitz Chayess I, end Ch. 10) suggests these are not related to the first seven, nor based on Scripture, but were passed down by oral tradition. The number thirty derives from the statement of the Talmudic sage Ulla in tractate Hullin 92a, though he lists only three other rules in addition to the original seven, consisting of the prohibitions against homosexuality and cannibalism, as well as the imperative to honor the Torah.
Talmud commentator Rashi remarks on this that he does not know the other Commandments that are referred to. Though the authorities seem to take it for granted that Ulla's thirty commandments included the original seven, an additional thirty laws is also possible from the reading.
The tenth century Shmuel ben Hophni Gaon lists thirty Noahide Commandments based on Ulla's Talmudic statement, though the text is problematic. He includes the prohibitions against suicide and false oaths, as well as the imperatives related to prayer, sacrifices and honoring one's parents.
The contemporary Rabbi Aaron Lichtenstein counts 66 instructions but Rabbi Harvey Falk has suggested that much work remains to be done in order to properly identify all of the Noahide Commandments, their divisions and subdivisions.
Theft, robbery and stealing covers the appropriate understanding of other persons, their property and their rights. The establishment of courts of justice promotes the value of the responsibility of a corporate society of people to enforce these laws and define these terms. The refusal to engage in unnecessary lust or cruelty demonstrates respect for the creation itself as renewed after the Flood. To not do murder would include human sacrifice.
From the perspective of traditional halakhah, if a non-Jew is to be accepted to live among the Jewish people in the Land of Israel, then that person must keep the Noahide Laws, and a number of additional Laws and regulations apply as well. Such as person is called a Ger Toshav "Sojourning Alien" amid the people of Israel. A "Ger Toshav" is the only kind of non-Jew who Jewish law permits to live among the Jewish people in the Land of Israel when the land is run according to Halacha and there is a Sanhedrin and a Temple. Jewish law only allows the official acceptance of a "Ger Toshav" as a sojourner in the Land of Israel during a time when the Year of Jubilee (yovel) is in effect.
A Ger Toshav should not be confused with a Ger Tzedek. A Ger Tzedek is a person who prefers to proceed to total conversion to Judaism, a procedure that is traditionally discouraged by Judaism and allowed to take place only after much thought and deliberation over converting.
Some modern views hold that penalties are a detail of the Noahide Laws and that Noahides themselves must determine the details of their own laws for themselves. According to this school of thought - see N. Rakover, Law and the Noahides (1998); M. Dallen, The Rainbow Covenant (2003)- the Noahide Laws offer mankind a set of absolute values and a framework for righteousness and justice, while the detailed laws that are currently on the books of the world's states and nations are presumptively valid.
Support for the spread of the Seven Noahide Commandments by the Druze leaders reflects the Biblical narrative itself. The Druze community reveres the non-Jewish father-in-law of Moses, Jethro, whom Arabs call Shoaib. According to the Biblical narrative, Jethro joined and assisted the Jewish people in the desert during the Exodus, accepted monotheism, but ultimately rejoined his own people. In fact, the tomb of Jethro in Tiberias is the most important religious site for the Druze community.
The 18th century rabbi, Jacob Emden proposed that Jesus, and Paul after him, intended to convert the gentiles to the Noahide laws while allowing the Jews to follow full Mosaic Law.