1 Samuel 18:3

Therefore thou shalt deal kindly with thy servant; for thou hast brought thy servant into a covenant of the LORD with thee: notwithstanding, if there be in me iniquity, slay me thyself; for why shouldest thou bring me to thy father? And Jonathan said, Far be it from thee: for if I knew certainly that evil were determined by my father to come upon thee, then would not I tell it thee? Then said David to Jonathan, Who shall tell me? or what if thy father answer thee roughly? And Jonathan said unto David, Come, and let us go out into the field. And they went out both of them into the field. And Jonathan said unto David, O LORD God of Israel, when I have sounded my father about to morrow any time, or the third day, and, behold, if there be good toward David, and I then send not unto thee, and show it thee; The LORD do so and much more to Jonathan: but if it please my father to do thee evil, then I will show it thee, and send thee away, that thou mayest go in peace: and the LORD be with thee, as he hath been with my father. And thou shalt not only while yet I live show me the kindness of the LORD, that I die not: But also thou shalt not cut off thy kindness from my house for ever: no, not when the LORD hath cut off the enemies of David every one from the face of the earth. So Jonathan made a covenant with the house of David, saying, Let the LORD even require it at the hand of David's enemies. And Jonathan caused David to swear again, because he loved him: for he loved him as he loved his own soul.

And they two made a covenant before the LORD: and David abode in the wood, and Jonathan went to his house.

And David said, Is there yet any that is left of the house of Saul, that I may show him kindness for Jonathan's sake? And there was of the house of Saul a servant whose name was Ziba. And when they had called him unto David, the king said unto him, Art thou Ziba? And he said, Thy servant is he. And the king said, Is there not yet any of the house of Saul, that I may show the kindness of God unto him? And Ziba said unto the king, Jonathan hath yet a son, which is lame on his feet.

But the king spared Mephibosheth, the son of Jonathan the son of Saul, because of the LORD's oath that was between them, between David and Jonathan the son of Saul.