1 Samuel 21:10-15

10Then David arose and fled that day from Saul, and went to 1Achish king of Gath. 11But the 2servants of Achish said to him, “Is this not David the king of the land? 3Did they not sing of this one as they danced, saying, ‘Saul has slain his thousands, And David his ten thousands’?” 12David 4took these words 5to heart and greatly feared Achish king of Gath. 13So he 6disguised his sanity before them, and acted insanely in their hands, and scribbled on the doors of the gate, and let his saliva run down into his beard. 14Then Achish said to his servants, “Behold, you see the man behaving as a madman. Why do you bring him to me? 15Do I lack madmen, that you have brought this one to act the madman in my presence? Shall this one come into my house?”