Jesse and his sons assumed leadership was about stature and strength. But God had a different plan for Israel's king.
The selection of David as king wasn't based on his being the eldest, strongest, or most skilled warrior among his brothers. In fact, he was so overlooked that he wasn't even present when his father initially presented his sons.
This highlights God's sovereignty. He chooses whom He wills, often the unexpected ones, to accomplish His purposes. David's calling to be king came directly from God's voice, overriding human expectations and family lineage.
God's declaration, 'Arise, anoint him, for this is he,' is definitive. It's God's direct intervention, setting in motion a plan that would shape the future of Israel and lead to the lineage of the Messiah.