10 Amasa was not on his guard against the dagger in Joab's hand, and Joab plunged it into his belly, and his intestines spilled out on the ground. Without being stabbed again, Amasa died. Then Joab and his brother Abishai pursued Sheba son of Bikri. 11 One of Joab's men stood beside Amasa and said, "Whoever favors Joab, and whoever is for David, let him follow Joab!" 12 Amasa lay wallowing in his blood in the middle of the road, and the man saw that all the troops came to a halt there. When he realized that everyone who came up to Amasa stopped, he dragged him from the road into a field and threw a garment over him. 13 After Amasa had been removed from the road, everyone went on with Joab to pursue Sheba son of Bikri.
10 But Amasa took no heed to the sword that was in Joab's hand: so he smote him therewith in the fifth rib, and shed out his bowels to the ground, and struck
10 But Amasa did not observe the sword that was in Joab's hand. So Joab struck him with it in the stomach and spilled his entrails to the ground without striking a second blow, and he died. Then Joab and Abishai his brother pursued Sheba the son of Bichri. 11 And one of Joab's young men took his stand by Amasa and said, "Whoever favors Joab, and whoever is for David, let him follow Joab." 12 And Amasa lay wallowing in his blood in the highway. And anyone who came by, seeing him, stopped. And when the man saw that all the people stopped, he carried Amasa out of the highway into the field and threw a garment over him. 13 When he was taken out of the highway, all the people went on after Joab to pursue Sheba the son of Bichri.
10 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. 11 One of Joab's soldiers took up his post over the body and called out, "Everyone who sides with Joab and supports David, follow Joab!" 12 Amasa was lying in a pool of blood in the middle of the road; the man realized that the whole army was going to stop and take a look, so he pulled Amasa's corpse off the road into the field and threw a blanket over him so it wouldn't collect spectators. 13 As soon as he'd gotten him off the road, the traffic flowed normally, following Joab in the chase after Sheba son of Bicri.
10 But Amasa did not notice the sword that was in Joab's hand. And he struck him with it in the stomach, and his entrails poured out on the ground; and he did not strike him again. Thus he died. Then Joab and Abishai his brother pursued Sheba the son of Bichri. 11 Meanwhile one of Joab's men stood near Amasa, and said, "Whoever favors Joab and whoever is for David--follow Joab!" 12 But Amasa wallowed in his blood in the middle of the highway. And when the man saw that all the people stood still, he moved Amasa from the highway to the field and threw a garment over him, when he saw that everyone who came upon him halted. 13 When he was removed from the highway, all the people went on after Joab to pursue Sheba the son of Bichri.
10 Amasa didn't notice the dagger in his left hand, and Joab stabbed him in the stomach with it so that his insides gushed out onto the ground. Joab did not need to strike again, and Amasa soon died. Joab and his brother Abishai left him lying there and continued after Sheba. 11 One of Joab's young men shouted to Amasa's troops, "If you are for Joab and David, come and follow Joab." 12 But Amasa lay in his blood in the middle of the road, and Joab's man saw that everyone was stopping to stare at him. So he pulled him off the road into a field and threw a cloak over him. 13 With Amasa's body out of the way, everyone went on with Joab to capture Sheba son of Bicri.
Matthew Henry's Commentary on 2 Samuel 20:10-13
Commentary on 2 Samuel 20:4-13
(Read 2 Samuel 20:4-13)
Joab barbarously murdered Amasa. The more plot there is in a sin, the worse it is. Joab contentedly sacrificed the interest both of the king and the kingdom to his personal revenge. But one would wonder with what face a murderer could pursue a traitor; and how, under such a load of guilt, he had courage to enter upon danger: his conscience was seared.