4 And Jonathan spoke well of David to Saul his father, and said to him, "Let not the king sin against his servant David; because he has not sinned against you, and because his deeds have been of good service to you; 5 for he took his life in his hand and he slew the Philistine, and the Lord wrought a great victory for all Israel. You saw it, and rejoiced; why then will you sin against innocent blood by killing David without cause?" 6 And Saul hearkened to the voice of Jonathan; Saul swore, "As the Lord lives, he shall not be put to death."
Matthew Henry's Commentary on 1 Samuel 19:4-6
Commentary on 1 Samuel 19:1-10
(Read 1 Samuel 19:1-10)
How forcible are right words! Saul was, for a time, convinced of the unreasonableness of his enmity to David; but he continued his malice against David. So incurable is the hatred of the seed of the serpent against that of the woman; so deceitful and desperately wicked is the heart of man without the grace of God, Jeremiah 17:9.