1 Samuel 20:15
And don't stop showing your gracious love to my family forever, not even when the LORD eliminates each of David's enemies from the surface of the earth."
2 Samuel 21:7
So the king answered, "I will give them." The king exempted Mephibosheth, the son of Saul's son Jonathan, because of the promise to the LORD that existed between David and Saul's son Jonathan.
1 Samuel 24:21
Now swear to me by the LORD that you will never eliminate my descendants after me, and that you won't erase my name from my father's family."
2 Samuel 9:1-7
Later on, David asked, "Is there anyone left alive from Saul's household to whom I can show gracious love in memory of Jonathan?"