David Must Die!
A Period Of Stalemate Is Followed By A Period In Which Saul Is Determined That David Must Definitely Die, Which Results In David Taking Refuge With Samuel.
Saul, obsessed with jealousy and fears for his throne could only view David's continuing growth in popularity with suspicion. He was aware that he himself had been rejected by YHWH, and that YHWH already had his successor in sight, and he clearly thought that David was the one. He therefore began to scheme as to how he could get rid of David, before David got rid of him.
Initially this led to his discussing the need for David to die with his son Jonathan and his other advisers and courtiers (1 Samuel 19:1). We are given no details but presumably Saul must have been suggesting that he was guilty of treason. In the end, however, Jonathan managed to talk him round. But the problem was that David continued to be militarily successful, and this simply renewed Saul's suspicions, for he was sick in mind. The result was that he made further attempts on David's life, firstly when he was playing for him because he was having ‘one of his turns', and then more systematically when he sought to have David arrested, presumably on a charge of treason. He had become obsessed with the thought that David must die.
Finally, recognising his parlous position, David sought help from his mentor Samuel, who was still a name in the land, for he was still the prophet of YHWH. And when Saul again sought to have him arrested, and finally went in order to do the job himself, God intervened and prevented all his attempts through irresistible acts of power.