Gregory of Nyssa

But this is marvelous not only for the fact that he grants life to the one who is doing everything against his life, but because David, although he had been anointed to the office of king and knew that he would not otherwise partake of that position unless Saul were out of the way, judged it better to suffer ill patiently in his private low estate than to enter upon the kingship by satisfying his anger against the one who had caused him grief.