How did Israel & Iran go from being allies to enemies?

Iran was one of the first Islamic nations to recognise Israel after it was founded in 1948. Notably, after Arab nations boycotted Israel after Six-Day War, Iran supplied it with crude oil. However, after the 1979 revolution brought Ayatollah Ruhollah Khomeini to power, Iran scrapped ties with Israel. In 2020, Ayatollah Ali Khamenei called Israel a 'cancerous tumour'.