1 Samuele 19:11

Saul also sent messengers unto David's house, to watch him, and to slay him in the morning: and Michal David's wife told him, saying, If thou save not thy life to night, to morrow thou shalt be slain. To slay him in the morning - When they might be able to distinguish between him and Michal his wife; for, had they attempted his life in the night season, there would have been some danger to Michal's life. Besides, Saul wished to represent him as a traitor; and consequently an attack upon him was justifiable at any time, even in the fullest daylight.