The Philistines gathered their armies together Sir Isaac Newton judges that they were recruited about this time by vast numbers of men driven out of Egypt by Amasis. This probably was one reason why they resolved on a new war with Israel, to which, however, Samuel's death and David's disgrace were doubtless additional motives. Achish said to David, Thou shalt go out with me to battle Achish formed this resolution in consequence of his knowledge of David's merit, and the thorough confidence he had in his fidelity.
Related Commentaries of 1 Samuel 28:1
1 Samuel 28:1
1 And it came to pass in those days, that the Philistines gathered their armies together for warfare, to fight with Israel. And Achish said unto David, Know thou assuredly, that thou shalt go out with me to battle, thou and thy men.