1 Samuel 20:31 (KJV)

And he said, Let me go, I pray thee; for our family hath a sacrifice in the city; and my brother, he hath commanded me to be there: and now, if I have found favour in thine eyes, let me get away, I pray thee, and see my brethren. Therefore he cometh not unto the king’s table.

Then Saul’s anger was kindled against Jonathan, and he said unto him, Thou son of the perverse rebellious woman, do not I know that thou hast chosen the son of Jesse to thine own confusion, and unto the confusion of thy mother’s nakedness?

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.