David and Jonathan

In chapters 19 and 20, in the book of 1 Samuel, David was persecuted by the Israelite king Saul.

Saul had a son named Jonathan, who had taken quite a liking to David.  Suffice it to say, Jonathan loved David more than he loved himself.  In these chapters, Saul tries to have David killed several times but David escapes.

Oddly enough, even when Jonathan confronted his father that David's actions only made him look better, Saul vowed not to kill David--then, in the next breath, an evil spirit had entered him and he was back to his murderous rage once again.

As a final test, there was a festival where David was supposed to sit next to Saul.  David hid in the fields and Jonathan was to advise David what the king's reaction would be.  When Saul became outraged, Jonathan knew David once again needed to flee from Saul.