At the beginning of Sefer Melachim (The Book of Kings,) we see David as an old man who can’t even keep himself warm. His son Adoniyah counts on his father’s decrepitude to usurp David’s chosen successor Shlomo (Solomon.) Suddenly David rises up, puts Shlomo on his mule, anoints him, and issues him decrees for unfinished business. It’s possible that David’s apparent frailty was actually a ruse to tempt potential conspirators to act prematurely, and it succeeds. This also provides Shlomo the pretext to eliminate Yoav (Joab,) something David had always wanted to do.