What is the worlds oldest monotheistic religion

Judaism
Judaism (from Latin: Iudaismus, derived from Greek Ἰουδαϊσμός, originally from Hebrew יהודה, Yehudah, "Judah"; in Hebrew: יהדות, Yahadut, the distinctive characteristics of the Judean ethnos) encompasses the religion, philosophy, culture and way of life of the Jewish people.

Judaism is an ancient monotheistic religion, with the Torah as its foundational text (part of the larger text known as the Tanakh or Hebrew Bible), and supplemental oral tradition represented by later texts such as the Midrash and the Talmud. Judaism is considered by religious Jews to be the expression of the covenantal relationship that God established with the Children of Israel.

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