1 Samuel 20:14-18

And if I am still alive, will you not show me the faithfulness of the Lord, so that I do not die?

And you shall never cut off your loyalty to my house, not even when the Lord cuts off every one of the enemies of David from the face of the earth.”

So Jonathan made a covenant with the house of David, saying, “May the Lord demand it from the hands of David’s enemies.”

And Jonathan made David vow again because of his love for him, because he loved him as he loved his own life.

Then Jonathan said to him, “Tomorrow is the new moon, and you will be missed since your seat will be empty.