David Musters with the Philistines

1 Samuel 28:1-2

And it cometh to pass in those days, that the Philistines gather their camps for the war, to fight against Israel, and Achish saith unto David, `Thou dost certainly know that with me thou dost go out into the camp, thou and thy men.'

And David saith unto Achish, `Therefore--thou dost know that which thy servant dost do.' And Achish saith unto David, `Therefore--keeper of my head I do appoint thee all the days.'