David was disparing that one day Saul would kill him and so made up his mind to escape, leave the people of God and go and live amongst the ungodly Philistines. t this point David was so low that he had forgotten the promises of the Lord towards him how he would one day be king and that Saul would not take his life. However David did not go alone to Gath in Philistia but took all his men and their families with him, so much depends upon godly leaders walking with the Lord that when they depart from the way many folow them. David goes to the king of Gath and asks for a city to dwell in and the king gives him Ziklag, for this David declared himself to be a servant of the king, what a sad time this must have been, that the champion of the armies of Israel was now the servant of the king of the philistines. During this time David leared to play the instrument of Gath as ssen in the titels of Psalm 8, 84 and 87 but he didn't write any Psalms to the Lord during this time, sadly he became a marauder and attacked cities and robbed their dead.
