1 Samuel 21:13

13 So he changed his behavior before them; he pretended to be mad when in their presence. He scratched marks on the doors of the gate, and let his spittle run down his beard.

1 Samuel 21:13 In-Context

11 The servants of Achish said to him, "Is this not David the king of the land? Did they not sing to one another of him in dances, "Saul has killed his thousands, and David his ten thousands'?"
12 David took these words to heart and was very much afraid of King Achish of Gath.
13 So he changed his behavior before them; he pretended to be mad when in their presence. He scratched marks on the doors of the gate, and let his spittle run down his beard.
14 Achish said to his servants, "Look, you see the man is mad; why then have you brought him to me?
15 Do I lack madmen, that you have brought this fellow to play the madman in my presence? Shall this fellow come into my house?"

Footnotes 1

New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.