Is it possible that the titles ‘ben David’ and ‘ben Yoseph’ do not refer to blood kinship or origin, but serve as a reference to the fact that someone possesses certain qualities, traits, abilities or characteristics such as the one to which one is named? Maybe they should be taken as descriptions rather as real names?
Let me clarify this a little bit.
Although the term ‘ben (בן)’ means ‘son’ or ‘son of’ in Hebrew, it’s also used sometimes almost as a Hebrew idiom for “one characterized by or connected with”, to indicate that someone possesses a certain ability, trait, quality, characteristic etc. or belongs to a certain group. בן-חיל, or בן-עולה, בןמשק, בני הנביאים to name some from the Tenach or בן-ברית, בן-בית.
We also know of the phenomenon that when a person has certain particularly dominant character traits that, in time, one’s name can become a title for such traits. Think of Einstein when someone is really smart or acts smart, think of Samsonite to emphasize the strength of a particular material. This is somewhat similar to the title with which Haman is described: Agagi, despite the fact that it is hard to say that Haman was a biological descendant of Agag/Amalek, but rather that his wicked characteristics and actions were reminiscent of those of Amalek. We even see people named after animals, kind of as a shem to’ar, to describe certain characteristics to them. The Tenach compares Leah with a cow for example, while comparing Rachel to a sheep.
If we take Mashiach ben David for example it could mean that Mashiach is comparable to David in his kingship. Which does not exclude that Messiah should be a literal son of David, since every king after David had to come from his bloodline.
So to sum things up:
Why do the titles ‘ben David’ and ‘ben Yoseph’ has to imply that they are from the bloodline of Yehudah and Ephraim, why can’t these be seen as descriptions?