1 Samuel 21:10-15

“Oh,” said David, “there’s no sword like that! Give it to me!” And at that, David shot out of there, running for his life from Saul. He went to Achish, king of Gath. When the servants of Achish saw him, they said, “Can this be David, the famous David? Is this the one they sing of at their dances? Saul kills by the thousand, David by the ten thousand!” When David realized that he had been recognized, he panicked, fearing the worst from Achish, king of Gath. So right there, while they were looking at him, he pretended to go crazy, pounding his head on the city gate and foaming at the mouth, spit dripping from his beard. Achish took one look at him and said to his servants, “Can’t you see he’s crazy? Why did you let him in here? Don’t you think I have enough crazy people to put up with as it is without adding another? Get him out of here!”