"The Devil was an archangel once"

Michael the Archangel triumphing over Satan (Revelation 12).
Creative Commons Attribution Share AlikeMichael the Archangel triumphing over Satan (Revelation 12). - Credit: Hawobo
See Bookmark for page 45 for further explanation of this statement.

An archangel is a chief angel. Only three are named in Scripture: Michael (mentioned in Daniel, Jude, and Revelation), Gabriel (mentioned in Daniel and Luke), and Lucifer (mentioned in Isaiah).