Self-identification
Judaism's purpose is to carry out what it holds to be the only Covenant between God and the Jewish people. The Torah (lit. "teaching"), both written and oral, tell the story of this covenant, and provides Jews with the terms of the covenant. The Oral Torah is the primary guide for Jews to abide by these terms, as expressed in tractate Gittin 60b, "the Holy One, Blessed be He, did not make His covenant with Israel except by virtue of the Oral Law" to help them learn how to live a holy life, and to bring holiness, peace and love into the world and into every part of life, so that life may be elevated to a high level of kedushah, originally through study and practice of the Torah, and since the destruction of the Second Temple, through prayer as expressed in tractate Sotah 49a "Since the destruction of the Temple, every day is more cursed than the preceding one; and the existence of the world is assured only by the kedusha...and the words spoken after the study of Torah." Since the adoption of the Amidah, the acknowledgement of God through the declaration from Yishayah 6:3 "Kadosh, kadosh, kadosh, is HaShem, Master of Legions; the whole world is filled with His glory". as a replacement for the study of Torah, which is a daily obligation for a Jew, and sanctifies God in itself. This continuous maintenance of relationship between the individual Jew and God through either study, or prayer repeated three times daily, is the confirmation of the original covenant. This allows the Jewish people as a community to strive and fulfill the prophecy "I, the Lord, have called you in righteousness, and will hold your hand and keep you. And I will establish you as a Covenant of the people, for a light unto the nations." (Isa 42:6 (i.e., a role model) over the course of history, and a part of the divine intent of bringing about an age of peace and sanctity where ideally a faithful life and good deeds should be ends in themselves, not means. See also Jewish principles of faith.
The self-described purpose of Christianity is to provide people with what it holds to be the only valid path to salvation as announced by the apostles of what the Book of Acts describes as, The Way. Only in gentile (non-Jewish) settings is The Way referred to as Christian. According to Christian theologian Alister McGrath, the Jewish Christians affirmed every aspect of then contemporary Second Temple Judaism with the addition of the belief that Jesus was the messiah, with Isaiah 49:6, "an explicit parallel to 42:6" quoted by Paul in Acts 13:47 and reinterpreted by Justin the Martyr. According to Christian writers, most notably Paul, the Bible teaches that people are, in their current state, sinful, and the New Testament reveals that Jesus is both the Son of man and the Son of God, united in the hypostatic union, God the Son, God made incarnate; that Jesus' death by crucifixion was a sacrifice to atone for all humanity's sins, and that acceptance of Jesus as Savior and Lord saves one from Divine Judgment, giving Eternal life. Jesus is the mediator of the New Covenant. His famous Sermon on the Mount is considered by some Christian scholars to be the proclamation of the New Covenant ethics, in contrast to the Mosaic Covenant of Moses from Mount Sinai. See also Christian theology.
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