Religious conversion is the adoption of new religious beliefs that differ from the convert's previous beliefs; in some cultures (e.g. Judaism) conversion also signifies joining an ethnic group as well as adopting that group's religious beliefs. A person who has undergone conversion is called a convert.

Conversion requires internalization of the new belief system.

Table of contents
1 Conversion to Judaism
2 Differences between Jewish and Christian views
3 Conversion to Christianity
4 Conversion to Islam

Conversion to Judaism

The Tanakh (Hebrew Bible) states that converts deserve special attention. The Hebrew word for "convert", ger, is the same as that for a stranger. It is also related to the root gar - "to dwell'. Hence since the Children of Israel were "strangers" - geirim in Egypt, they are therefore instructed to be welcoming to those who seek to convert and dwell amongst them.

Jewish law has strict guidelines for accepting new converts to Judaism. According to Jewish law, which is still followed as normative by Orthodox Judaism and Conservative Judaism, potential converts must want to convert to Judaism for its own sake, and for no ulterior motives. A male convert needs to undergo a ritual circumcision , and there has to be a commitment to observe Jewish law. A convert must accept Jewish principles of faith, and reject the previous theology that he or she had prior to the conversion. Ritual immersion in a small pool of water known as a mikveh is required , and the convert takes a new Jewish name and is considered to be a son or daughter of the biblical patriarch Abraham.

The most famous Jewish King , King David was descended from the convert Ruth a princess from Moab . The father of the most famous sage of the Talmud, Rabbi Akiva, was a convert. Christians were forbidden to convert to Judaism on pain of death during most of the Middle Ages. In the 1700s a famous convert by the name of Count Valentin Potoski in Poland was burned at the stake. He was a disciple of Rabbi Elijah, known as the Vilna Gaon .

Some Jewish people are also descended from converts to Judaism outside the Mediterranean world. It is known that some Khazars, Edomites, and Ethiopians, as well as many Arabs, particularly in Yemen before, converted to Judaism in the past; today in the United States and Israel some people still convert to Judaism. In fact, there is a greater tradition of conversion to Judaism than many people realize. The word "proselyte" originally meant a Greek who had converted to Judaism. As late as the 6th century the rump Roman empire (ie Byzantium) was issuing decrees against conversion to Judaism, implying that conversion to Judaism was still occurring.

The Reform Judaism and Conservative Judaism movements are lenient in their acceptance of converts. Many of their members are married to non-Jews, and these movements make an effort to welcome the spouses of Jews who seek to convert. This issue is a lightening rod in modern day Israel as many immigrants from the former Soviet Union are not Jewish.

Since around 300 CE, Judaism has stopped encouraging people to join its faith. In fact, converts are often discouraged from becoming Jews and warned that being a Jew entails great risks such as becoming a victim of Anti-Semitism.

Differences between Jewish and Christian views

Judaism does not characterize itself as a religion (although one can speak of the Jewish religion and religious Jews). The subject of the Tanach (Hebrew Bible) is the history of the Children of Israel (also called Hebrews), especially in terms of their relationship with God. Thus, Judaism has also been characterized as a culture or as a civilization. Rabbi Mordecai Kaplan defines Judaism as an evolving religious civilization. One crucial sign of this is that one need not believe, or even do, anything to be Jewish; the historic definition of 'Jewishness' requires only that one be born of a Jewish mother, or that one convert to Judaism in accord with Jewish law. (Today, Reform and Reconstructionist Jews also include those born of Jewish fathers and gentile mothers if the children are raised as Jews.)

To Jews, Jewish peoplehood is closely tied to their relationship with God, and thus has a strong theological component. This relationship is encapsulated in the notion that Jews are a chosen people. Although many non-Jews have taken this as a sign of arrogance or exclusivity, Jewish scholars and theologians have emphasized that a special relationship between Jews and God does not in any way preclude other nations having their own relationship with God. For Jews, being "chosen" fundamentally means that Jews have chosen to obey a certain set of laws (see Torah and halakha) as an expression of their covenant with God. Jews hold that other nations and peoples are not required or expected to obey these laws, and face no penalty for not obeying them. Thus, as a national religion, Judaism has no problem with the notion that others have their own paths to God (or "salvation").

Christianity, on the other hand, is characterized by its claim to universality, which marks a break with Jewish identity. As a religion claiming universality, Christianity has had to define itself in relation with religions that make radically different claims about Gods. Christians believe that Christianity represents the fulfillment of God's promise to Abraham and the nation of Israel, that Israel would be a blessing to all nations.

This crucial difference between the two religions has other implications. For example, conversion to Judaism is more like a form of adoption (i.e. becoming a member of the nation, in part by metaphorically becoming a child of Abraham), whereas conversion to Christianity is explicitly a declaration of faith. Depending on the denomination, this conversion has a social component, as the individual is in many ways adopted into the Church, with a strong family model.

Conversion to Christianity

In the times of Jesus, gentiles who sought to join him were required to undergo conversion to Judaism first including circumcision for men. This requirement was later dropped after Paul forced the issue.

The origin of Christian Baptism in water is derived from the Jewish law requiring a convert to submerege themselves in pure water in order to receive a new pure soul from God. It was only many years after Jesus, that there was split in the movement and those seeking to convert to Christianity were not faced with the major obstacles that Judaism presented.

Christianity and Islam are two religions that encourage preaching their faith in order to convert non-believers. In both cases, this missionary property has been used as an excuse for religious wars (crusades) on other countries.

In the year 1000, the Viking age parliament of Iceland decided that the entire country should convert to Christianity, and that sacrifice to the old gods, while still allowed, should no longer be made in the open. Similar mass conversions in other Scandinavian countries were not as democratic.

See also: Proselytism

Conversion to Islam

(to be written)

See also secondary conversion.