1 Samuel 20:33 (KJV)

For as long as the son of Jesse liveth upon the ground, thou shalt not be established, nor thy kingdom. Wherefore now send and fetch him unto me, for he shall surely die.

And Jonathan answered Saul his father, and said unto him, Wherefore shall he be slain? what hath he done?

And Saul cast a javelin at him to smite him: whereby Jonathan knew that it was determined of his father to slay David.

So Jonathan arose from the table in fierce anger, and did eat no meat the second day of the month: for he was grieved for David, because his father had done him shame.

And it came to pass in the morning, that Jonathan went out into the field at the time appointed with David, and a little lad with him.