2 Samuel 20:4-10

The king ordered Amasa, “Muster the men of Judah for me in three days; then report in.” Amasa went to carry out his orders, but he was late reporting back. So David told Abishai, “Sheba son of Bicri is going to hurt us even worse than Absalom did. Take your master’s servants and hunt him down before he gets holed up in some fortress city where we can’t get to him.” So under Abishai’s command, all the best men—Joab’s men and the Kerethites and Pelethites—left Jerusalem to hunt down Sheba son of Bicri. They were near the boulder at Gibeon when Amasa came their way. Joab was wearing a tunic with a sheathed sword strapped on his waist, but the sword slipped out and fell to the ground. Joab greeted Amasa, “How are you, brother?” and took Amasa’s beard in his right hand as if to kiss him. Amasa didn’t notice the sword in Joab’s other hand. Joab stuck him in the belly and his guts spilled to the ground. A second blow wasn’t needed; he was dead. Then Joab and his brother Abishai continued to chase Sheba son of Bicri.