This rhetorical question indicates that the king does not think they should go along with him. This question can be written as a statement. AT: "You do not need to go with us." (See: [[rc://en/ta/man/translate/figs-rquestion]])
This rhetorical question emphasizes David did not want Ittai to come. This question can be translated as a statement. AT: "I do not want to cause you to wander around with us." (See: [[rc://en/ta/man/translate/figs-rquestion]])
Here "yesterday" is an exaggeration that emphasizes a short amount of time. Ittai the Gittite had lived there for several years. AT: "Since you have lived here only a short time" (See: [[rc://en/ta/man/translate/figs-hyperbole]])