get thee behind me

(idiomatic) Do not tempt or torment me; I reject you, your statements, or your beliefs.

Example: 1824, Sir Walter Scott, Redgauntlet, ch. 16:
  "Jesu Maria!" exclaimed the younger. "Oh, fie, Sister Seraphina! Fie, fie!--VADE RETRO--get thee behind me!"
1904, Jerome K. Jerome, Tommy and Co., ch. 4:
  Peter most assuredly would have risen in his wrath, would have said to his distinguished-looking temptress, "Get thee behind me, Miss Ramsbotham."
1998 Oct. 15, Tony Karon, "Postmodern Papacy?," Time (retrieved 25 Aug 2015):
  Get thee behind me, Derrida! Skeptical postmodernists may have reduced the certainties of Western intellectual life to a pile of gaudy plastic tchotchkes, but Pope John Paul II is fighting back.
2005 Nov. 26, Ian Irvine, "btw," Independent (UK) (retrieved 25 Aug 2015):
  Get thee behind me, Santa. Curious news from Germany, where a group has launched a campaign to persuade people to turn their backs on Santa Claus and return to St Nicholas instead.