1 Samuel 29:9

As an angel of God - There is some reason to think that Achish had actually embraced or was favourably disposed towards the Jewish religion. He speaks here of the angels of God, as a Jew might be expected to speak; and in 1 Samuel 29:6 ; he appeals to, and swears by Jehovah; which, perhaps, no Philistine ever did. It is possible that he might have learned many important truths from David, during the time he sojourned with him.