13 So changing his behaviour before them, he made it seem as if he was off his head, hammering on the doors of the town, and letting the water from his mouth go down his chin. 14 Then Achish said to his servants, Look! the man is clearly off his head; why have you let him come before me? 15 Are there not enough unbalanced men about me, that you have let this person come and do such tricks before me? is such a man to come into my house?
Matthew Henry's Commentary on 1 Samuel 21:13-15
Commentary on 1 Samuel 21:10-15
(Read 1 Samuel 21:10-15)
God's persecuted people have often found better usage from Philistines than from Israelites. David had reason to put confidence in Achish, yet he began to be afraid. His conduct was degrading, and discovered wavering in his faith and courage. The more simply we depend on God, and obey him, the more comfortably and surely we shall walk through this troublesome world.