And now behold, I know that thou shalt certainly be king, and that the kingdom of Israel shall be established in thy hand.

'And, now, lo, I have known that thou dost certainly reign, and the kingdom of Israel hath stood in thy hand;

And now I am certain that you will be king, and that the kingdom of Israel will be made strong under your authority.

I know well that thou shalt surely be king - Hebrew, Reigning, thou shalt reign. He knew this before; and yet he continued to pursue him with the most deadly hatred.

And now, behold, I (g) know well that thou shalt surely be king, and that the kingdom of Israel shall be established in thine hand.
(g) Though this tyrant saw and confessed the favour of God toward David, yet he did not cease to persecute him against his own conscience.

And now, behold, I know well that thou shalt surely be king,.... Not merely by the common report, that he was anointed by Samuel, to which yet he might give credit; but by the providence of God prospering and preserving him, and by his princely spirit and behaviour, and by calling to mind what Samuel had said to him, that his kingdom should be given to a neighbour of his better than he, and so David was by his own confession, 1-Samuel 24:17; and the cutting off the skirt of his garment might put him in remembrance of the rending of the skirt of Samuel's mantle, upon which he told Saul his kingdom should be rent from him; though some think that was Saul's skirt, and so now he knew thereby, when David cut off his skirt, that the kingdom would be his; and it is a tradition of the Jews (f), that Samuel said to him at that time, that he that cut off the skirt of his garment should reign after him:
and that the kingdom of Israel shall be established in thine hand; and not be rent from him; and yet notwithstanding after this he sought to destroy him.
(f) Midrash Tillim apud Abarbinel. in loc.

This wish was expressed in perfect sincerity. David's behaviour towards him had conquered for the moment the evil demon of his heart, and completely altered his feelings. In this better state of mind he felt impelled even to give utterance to these words, "I know that thou wilt be king, and the sovereignty will have perpetuity in thy hand." Saul could not prevent this conviction from forcing itself upon him, after his own rejection and the failure of all that he attempted against David; and it was this which drove him to persecute David whenever the evil spirit had the upper hand in his soul. But now that better feelings had arisen in his mind, he uttered it without envy, and merely asked David to promise on oath that he would not cut off his descendants after his death, and seek to exterminate his name from his father's house. A name is exterminated when the whole of the descendants are destroyed, - a thing of frequent occurrence in the East in connection with a change of dynasties, and one which occurred again and again even in the kingdom of the ten tribes (vid., 1-Kings 15:28., 1-Samuel 16:11.; 2 Kings 10).