1 Samuel 21:11-15

11But the 1servants of Achish said to him, “Is this not David, the king of the land? 2Did they not sing of this one as they danced, saying, ‘Saul has slain his thousands, And David his ten thousands’?” 12David 3took these words 4to heart and greatly feared Achish king of Gath. 13So he 5disguised his sanity while in their sight and acted insanely in their 6custody, and he scribbled on the doors of the gate, and drooled on his beard. 14Then Achish said to his servants, “Look, you see the man is behaving like an insane person. Why do you bring him to me? 15Do I lack insane people, that you have brought this one to behave like an insane person in my presence? Shall this one come into my house?”