Didn't Saul know that Judah's line would rule?

Dear Rabbi Are you saying that everyone knew about this oral law of the messiah in the desert . So why did Saul not know about this and why did the people not turn to David and why did David have to turn to Ruth,Boaz and marry king Sauls daughter to maintainhis position. Something is not right. especially as Sauls son continued to reign confused mike

Shalom Mike, Good question, but as almost always, you're not the first to ask. It's very simple: Nachmanides answers that Jacob was careful in his wording: "the scepter shall not 'leave' Judah etc.", once it has come to Judah, but before it came to Judah's family (i.e. David), nobody knew how long that temporary line of Saul's would be (including Saul). David didn't know, and obviously the people didn't know that David would be that father of the Judaic kingdom's lineage, so they couldn't have turned to him. Check the text and you'll see that David didn't marry Saul's daughter in order to reign, and that Boaz and Ruth didn't know who from Judah would start the dynasty. With Love of Israel, Rav Ari Shvat