drew a line in the sand

Verb

draw a line in the sand (third-person singular simple present draws a line in the sand, present participle drawing a line in the sand, simple past drew a line in the sand, past participle drawn a line in the sand)

1. (intransitive) To lay down a challenge; to provide a test of commitment (often one which carries a high risk) to a cause.
   • "Well," Judd said, "what's the deal. You in or out?" "I have to decide right now?" "We have a meeting with Bruce tonight and church tomorrow morning. You go with us tonight and you promise to go tomorrow, or you move out this afternoon." "The man's drawing a line in the sand for you," Lionel said....1998, Jerry B. Jenkins with Tim F. LaHaye, Through the flames
2. To create a real or artificial boundary or distinction between (two places, people or things).
   • At some point you ask, "Where do we draw a line in the sand between deconstruction as desertification of God and as desertion of God?" There is no line.1999, John D. Caputo, Michael J. Scanlon, God, the Gift, and Postmodernism, page 133
3. To indicate the threshold or level above which something will become unacceptable or will provoke a response; to create a boundary and imply or declare that its crossing will provoke a (negative) response.
   • “A line has been drawn in the sand” against any Iraqi invasion of Saudi Arabia, Mr. Bush said.1990 August 9, R. W. Apple Jr, quoting George W. Bush, “Bush draws ‘line’”, in The New York Times, →ISSN