Elijah (Hebrew: אֱלִיָּהוּ, Eliyahu, meaning "My God is Yahu/Jah") or Elias (; Greek: Ηλίας Elías; Syriac: ܐܸܠܝܼܵܐ Elyāe; Arabic: إلياس or إليا, Ilyās or Ilyā) was a prophet and a miracle worker who lived in the northern kingdom of Israel during the reign of Ahab (9th century BC), according to the Books of Kings in the Hebrew Bible. In 1 Kings 18, Elijah defended the worship of the Jewish God over that of the Canaanite deity Baal. God also performed many miracles through Elijah, including resurrection (raising the dead), bringing fire down from the sky, and entering Heaven alive "by a whirlwind". He is also portrayed as leading a school of prophets known as "the sons of the prophets". Following his ascension, Elisha his disciple and most devoted assistant took over his role as leader of this school. The Book of Malachi prophesies Elijah's return "before the coming of the great and terrible day of the LORD", making him a harbinger of the Messiah and of the eschaton in various faiths that revere the Hebrew Bible. References to Elijah appear in Ecclesiasticus, the New Testament, the Mishnah and Talmud, the Quran, the Book of Mormon, the Doctrine and Covenants, and Bahá'í writings.
In Judaism, Elijah's name is invoked at the weekly Havdalah ritual that marks the end of Shabbat, and Elijah is invoked in other Jewish customs, among them the Passover Seder and the brit milah (ritual circumcision). He appears in numerous stories and references in the Haggadah and rabbinic literature, including the Babylonian Talmud.
The Christian New Testament notes that some people thought that Jesus was, in some sense, Elijah. But Jesus makes it clear that John the Baptist is "the Elijah" who was promised to come in Malachi 3:23 in the Septuagint. (Malachi 4:5 Elijah appears with Moses during the Transfiguration of Jesus. Elijah is also a figure in various Christian folk traditions, at times identified with earlier pagan thunder or sky gods.
In Islam, Elijah appears in the Quran as a prophet and messenger of God, where his biblical narrative of preaching against the worshipers of Baal is recounted in a concise form. Due to his importance to Muslims, Catholics and Orthodox Christians, Elijah has been venerated as the patron saint of Bosnia and Herzegovina since 1752.