Gideon (gĭdˈēən) [key], or Jerubbaal jērŭbˈāəl, –rəbāˈəl, in the Bible, a 12th-century Israelite warrior of the tribe of Mannasseh, and one of the greater judges of Israel. The Book of Judges relates that Gideon was a strong opponent of the Baal cult. He defeated the Midianite oppressors and appeased the rival Ephraimites, thus securing a generation of peace for Israel. His decisive action gave rise to the phrase "Day of Midian," which came to denote Israelite victory over her enemies. Gideon refused to institute an hereditary monarchy in Israel because of his belief that God was the king of Israel.