Jonathan said to David, Yahweh, the God of Israel, [be witness]: when I have sounded my father about this time tomorrow, [or] the third day, behold, if there be good toward David, shall I not then send to you, and disclose it to you?
"If I am still alive, show me the loyal love of the Lord, that I may not die"  (1 Samuel 20:16).  In these words it is clear that Jonathan recognized the grave danger to himself when God would take vengeance upon all of David's enemies.  Jonathan, through filial loyalty, would not desert his father even when that inevitable day of reckoning would come.