Demas or Demos was a man mentioned by the Apostle Paul in the New Testament of the Bible, and appears to have been involved for a time in his ministry.
Demas is mentioned in three of the canonical Pauline epistles:
Demas is also mentioned in the non-canonical Acts of Paul and Thecla, where he is described as holding views similar to the author of Second Peter. Based on this, Dale Martin speculates that whichever one of the Acts of Paul and Thecla and the Pastoral Epistles (including Second Timothy) was written later may have been arguing against the other.
In The Pilgrim's Progress, John Bunyan writes of Demas, a deceiver, who beckons to pilgrims at the Hill Lucre, urging them to join in the supposed silver mining being carried out there; he is described as a "fellow pilgrim", just as Demas is described by Paul as a "fellow worker," but has a love for earthly treasures which caused him to desert the path and could lead to his death, just as Demas's love for the world caused him to stop following God and potentially to lose his salvation.
In Shane Johnson's 2007 novel, "The Demas Revelation," Demas plays a pivotal role in the plot of the story and lends his name to the title.
In Jane Eyre, St. John notes that Jane is free of "the vice of Demas" when trying to convince her to join him as a missionary in India.