So Jonathan arose from the table in fierce anger, and did eat no food the second day of the month: for he was grieved for David, because his father had caused him shame.
All Commentaries on 1 Samuel 20:34 Go To 1 Samuel 20
Ambrose of Milan
AD 397
Who would not have loved him [David], when they saw how dear he was to his friends? For as he truly loved his friends, so he thought that he was loved as much in return by his own friends. No, parents put him even before their own children, and children loved him more than their parents. Therefore Saul was very angry and strove to strike Jonathan his son with a spear because he thought that David’s friendship held a higher place in his esteem than either filial piety or a father’s authority.