Christianity and Judaism are closely connected religions with shared origins, scriptures, and moral concerns. Both hold that there is a responsibility for human life to God and to people. Their relationship does not only have to be based upon similarities, though, as their understanding of religious authority, religious identity and salvation varies. Christianity emerged and grew out of Judaism and eventually grew into a distinct tradition with many non-Jewish adherents (Heyden and Nirenberg 159). Judaism evolved and gained its own traditions of interpretation and communal practice. Religions are not monolithic and a comparison should be made with awareness of the differences within the individual communities. Although Christianity and Judaism share historical roots and ethical values, they differ in their understanding of Jesus, religious authority, and worship.
First, both religions look to the God of Israel, but Jesus occupies a fundamentally different position in their beliefs. Fredriksen explains their historical connection: “Late Second Temple Judaism was the seedbed from which all later Christianities sprang” (1). This statement matters because Christianity did not begin as a religion disconnected from Jewish beliefs. Jesus and his early disciples were immersed in the Jewish religious tradition, with its texts and expectations of God's salvation. However, mainstream Christianity was able to see Jesus as the Messiah and divine Son whose death and resurrection brings salvation. Jesus was not Jesus the Messiah or God in flesh for the Jewish people. The Trinity – Father, Son and Holy Spirit – is the most common form of expression of the unity of God in most Christian traditions. This Christian expression does not fit with Jewish concepts of God's oneness. These differences shape how the traditions interpret redemption. Christians place Jesus at the center of their relationship with God, whereas Jewish religious life centers on the covenant between God and Israel without requiring faith in Jesus. However, the contrast should not imply that Christianity emerged fully formed. As Fredriksen demonstrates, early Christian identities and teachings developed through continuing arguments. Their shared beginnings therefore explain their close relationship, while their different claims about Jesus explain a central point of separation.
Second, Christianity and Judaism both treat scripture as authoritative, but they differ in how they organize and interpret that authority. The Jewish Tanakh contains the Torah, Prophets, and Writings. Christians receive these writings through their Old Testament traditions and also recognize the New Testament. Consequently, overlapping texts can carry different meanings because Christians frequently interpret them through Jesus, while Jewish interpretation does not depend on Christian claims. Interpretation also produces diversity within each religion. Fredriksen observes, “Intra-Jewish argument about the right way to be Jewish is a standard feature of Jewish texts” (13). Her observation challenges the assumption that Judaism is simply a fixed collection of rules. Debate itself forms part of its religious inheritance. Rabbinic Judaism developed extensive traditions of discussing how commandments apply to daily life, while Christian communities developed their own approaches to scripture, church teaching, and religious practice. Both therefore require interpretation rather than merely repeating ancient words. These differences should not erase internal variation: observance differs among Jewish communities, just as worship and authority differ among Christian denominations.
Third, both religions connect devotion to God with ethical responsibility, although they explain and express that responsibility through distinct traditions. The commentary in The Jewish Annotated New Testament states, “Love of God and neighbor have been central to Judaism since the Bible” (Levine and Brettler 344). This directly challenges the misleading contrast between a supposedly legalistic Judaism and a loving Christianity. Love is a concept that came out of the Jewish world, and it has been a part of their teachings long before the Christian message of love was introduced. Both traditions promote generosity, caring for those in need and doing good for the community. They are morally similar so they can work together without any need for them to agree on Jesus. Shared ethical objectives do not equate their religious practices, however. In general, Jewish law associates moral action with covenantal duty, and Christians almost always associate loving action with following Jesus and responding to grace from God. Both descriptions leave room for mercy and for obligations among Christians. The discussion above also makes it clear that Jewish love must be manifested in action; that religious feelings are not enough (344). In a similar way, our understanding of love in Christianity is given its most concrete and meaningful expression through service and accountability. In the best comparisons, therefore, common moral expectations are acknowledged, but so are differing religious explanations. These common duties serve as a framework for respectful relationships and help to ensure the distinct identity of each community.
Christianity and Judaism share more than historical contact: they draw on related scriptures as well as connect on religious commitment with responsibility toward others. Their differences are still significant, more so, in their understanding of scriptural interpretation. To grasp those differences, we need to be careful not to make the superficial distinction between love and rules when referring to different religions. A balanced comparison acknowledges the Jewish roots of Christianity and the Jewish nature of Judaism as a live tradition and its purposes. Their relationship can best be appreciated from their common roots and the different ways they conceive of faithful living in various communities throughout history.
