Conversion (ἐπιστρέφω, epistrephō, “change of mind”). In Judaism, refers to initiation into adherence to the Torah, especially by circumcision. In Christianity, refers to initiation into the Church of Christ, especially by baptism. In both, conversion refers to a turning from old ways to the practices of a new faith.
The conversion of a Gentile to the Jewish religion involved several rituals, the most distinct markers being circumcision, ritual immersion, participation in Jewish religious practices, and adherence to the Torah. The term “proselyte” (προσήλυτος, prosēlytos) was originally a Jewish term that referred only to someone in the process of becoming Jewish. The Hebrew term “sojourner” (גֵּר, ger) designated an abiding stranger or alien in the land. In time, the term developed to refer to a convert to Judaism.
In the Old Testament, the sojourner (גֵּר, ger) was a resident alien who lacked the protection afforded to natural born Jews. The Torah portrays sojourners as being in a special relationship with God—a relationship not specifically religious, but a result of the sojourner inhabiting the land of God’s influence (Exod 20:10; 22:21; 23:9, 12). Sojourners were included in many religious rituals and festivals (Deut 5:14; 16:11). Additionally, Deuteronomy 31:12 states that sojourners were to be present during the reading of the law so they could understand what was necessary to follow the Lord. In eschatological writings, sojourners will occupy a share of the promised land with the tribes of Israel (Ezek 47:22–23).
Various things were required of Jewish proselytes, including commitment to following the Torah, water immersion, sacrifices, and circumcision (Schiffman, Who Was a Jew?, 19). Sacrifices were no longer required after the destruction of the temple of Jerusalem in ad 70, but the other three practices remained (Schiffman, Who Was a Jew?, 30–31). It is possible that, prior to the late first century ad, neither baptism nor sacrifices were required of proselytes (Collins, “A Symbol of Otherness,” 163–165). The requirements for Jewish conversion likely varied at different points in antiquity, “so it is no longer accurate to speak of Judaism requiring circumcision, baptism, and sacrifice in the temple (replaced by almsgiving after the temple’s destruction)” (McKnight, “Proselytism and Godfearers,” 845). We can, however, be certain that circumcision, sacrifices, and ritual immersion were all components of Jewish proselytism at one time or another.
Jewish Proselytism and Christian Conversion
When the Christian Church began to accept Gentile converts, several questions arose regarding the process of conversion and whether Gentile Christians had to accept Jewish practices to be received into the Christian community. The Christian Church began as a sect of Judaism. This changed when God gave Peter and Cornelius the vision of the gospel spreading to the Gentiles (Acts 10). Prior to this, the Ethiopian eunuch, who was evidently a convert to Judaism, had converted to Christianity (Acts 8:26–39). The early church first understood that conversion to Christianity entailed being born Jewish or converting to Judaism—and being circumcised. The idea that Gentiles could become Christians without first becoming Jewish caused dissension among some in the church, particularly Christians who were previously Pharisees (Acts 15:1, 5).
The apostles convened the Jerusalem Council to discuss the requirements for new Gentile converts to Christianity (Acts 15). After some debate, the Apostle James concludes, “my judgment is that we should not trouble those of the Gentiles who turn to God, but should write to them to abstain from the things polluted by idols, and from sexual immorality, and from what has been strangled, and from blood” (Acts 15:19 ESV). This decree was the focus of a letter the apostles sent to the churches (Acts 15:22–29). The decree was also positively received by believers in Antioch (Acts 15:30–35). The Apostle Paul would later contend with so-called Judaizers who sought to impose further requirements upon Gentiles (Gal 2:4). In another instance, Paul contended that “circumcision of the heart” has effectively replaced physical circumcision: “In him also you were circumcised with a circumcision made without hands, by putting off the body of the flesh, by the circumcision of Christ, having been buried with him in baptism, in which you were also raised with him through faith in the powerful working of God, who raised him from the dead” (Col 2:11–12 ESV).
Conversion in Early Christianity
The Didache (ad 100) describes the process of conversion in the earliest church. The first six chapters form an ethical teaching of the “two-ways”—the way of life and the way of death. The way of life includes loving God first and foremost, the golden rule, praying for enemies, and abstinence from worldly lusts (Didache 1:2). The way of death is rife with sin, including murder, adultery, failure to help those in need, loving lies, and pursuing revenge (Didache 5:1–5). Would-be converts to the Christian faith needed to exemplify the new, positive characteristics and remember Christian teachings prior to their baptism (Didache 7:1).
Baptism serves as a turning point in the conversion process: Once the prospective Christian has rejected the way of death and been baptized, he or she gains full entrance into the Christian community and is responsible for participating in its rituals and practices. The rest of the Didache (8–16) describes the characteristics of Christian community, the observance of fasts and the Eucharist, gathering together on the Lord’s Day (Sunday), and the welcoming of other Christians in the name of the Lord. Conversion in the Didache can be seen as a two-stage process: first, the cognitive (understanding the teachings and the way of life) and then the ritual (participation in community life; Finn, From Death to Rebirth, 148). In other words, conversion in the Didache consists of first adhering to theological orthodoxy, and allowing this orthodoxy to manifest itself in faithful orthopraxy within the Christian community. Baptism is thus symbolic of washing the way of death with its sinful tendencies and a promise to adhere to the new way of life. In the Didache, one can easily see the ways in which Jewish practices influenced the conversion practices of the early Christians.
Collins, J.J. “A Symbol of Otherness: Circumcision and Salvation in the First Century.” Pages 163–86 in to See Ourselves as Others See Us. Edited by J. Neusner and E.S. Frerichs. Chico, Calif.: Scholars Press, 1985.
Finn, Thomas M. From Death to Rebirth: Ritual and Conversion in Antiquity. New York: Paulist Press, 1997.
Gaventa, Beverly Roberts. From Darkness to Light: Aspects of Conversion in the New Testament. Philadelphia, Pa.: Fortress, 1986.
Goodman, Martin. Mission and Conversion: Proselytizing in the Religious History of the Roman Empire. New York: Oxford University Press, 1996.
McKnight, Scot. A Light Among the Gentiles: Jewish Missionary Activity in the Second Temple Period. Minneapolis, Minn.: Fortress, 1991.
Schiffman, Lawrence H. Who Was a Jew? Rabbinic and Halakhic Perspectives on the Jewish Christian Schism. Hoboken, N.J.: Ktav Pub Inc., 1985.
Stern, Menahem. Greek and Latin authors on Jews and Judaism. 3d print ed. Jerusalem: Israel Academy of Sciences and Humanities, 1981.
Espinoza, B. (2016). Conversion. In J. D. Barry, D. Bomar, D. R. Brown, R. Klippenstein, D. Mangum, C. Sinclair Wolcott, … W. Widder (Eds.), The Lexham Bible Dictionary. Bellingham, WA: Lexham Press.