What does 1 Samuel 30:13 mean?

David asked him, 'Who do you belong to? Where are you from?' He answered, 'I’m an Egyptian, a slave of an Amalekite. My master left me behind three days ago because I got sick.' 1 Samuel 30:13 - Modern Text Bible

(The Egyptian explains he was abandoned by his Amalekite master, giving David a lead on the raiders.)