1 Samuel 18:20,21

The thing pleased him Not out of any love to David, or desire to perform his promise; but because he hoped, by her means, to bring his ends about of destroying David. That she may be a snare to him He hoped his daughter, in obedience to him, might be persuaded to bring him into some snare that he would lay for him: or that, being exposed to great dangers, (which he was to undergo, as a condition of having her to wife,) he might perish in some of them. Thou shalt be this day my son-in- law That is, shortly, within a little time. In the one of the twain Saul seems in this to have told David that though some reasons of state had obliged him to give his elder daughter to Adriel, yet still he would have him for his son-in-law, by giving the other unto him.