Then David asked, “How will I know whether or not your father is angry?”
“Come out to the field with me,” Jonathan replied. And they went out there together. Then Jonathan said to David, “I promise by the Lord, the God of Israel, that by this time tomorrow, or the next day at the latest, I will talk to my father and let you know at once how he feels about you. If he speaks favorably about you, I will let you know. But if he is angry and want you killed, may the Lord strike me and even kill me if I don’t warn you so you can escape and live. May the Lord be with you as he used to be with my father. And may you treat me with the faithful love of the Lord as long as I live. But if I die, treat my family with this faithful love, even when the Lord destroys all you enemies from the face of the earth.” (vv. 10-15, NLT)
So David hid himself in the field, and when the new moon festival began, the king sat down to eat. He sat at his usual place against the wall sitting opposite him and Abner beside him. But David’s place was empty. Saul didn’t say anything about it that day, for he had said to himself, “Something must have made David ceremonially unclean.” But the when David’s place was empty again the next day, Saul asked Jonathan, “Why hasn’t the son of Jess been here for the meal either yesterday or today?”
Jonathan replied, “David earnestly asked me if he could to Bethlehem. He said, ‘Please let me go, for we are having a family sacrifice. My brother demanded that I be there. So please let me get away to see my brothers.’ That’s why he isn’t here at the king’s table.”
Saul boiled with rage at Jonathan, “You stupid son of a whore!” he swore at him. “You think I don’t know that you want him to be king in your place, shaming yourself and your mother? As long as that son of Jesse is alive, you’ll never be king. No go and get him so I can kill him!”
“But why should he be put to death? Jonathan asked his father. “What has he done?” Then Saul hurled his spear at Jonathan, intending to kill him. So at last Jonathan realized that his father was really determined to kill David. (vv. 24-33, NLT)