10 And Amasa had taken no notice of the sword that was in Joab's hand: so he smote him with it in the belly and shed out his bowels to the ground, and struck him not again; and he died. And Joab and Abishai his brother pursued after Sheba the son of Bichri. 11 And one of Joab's young men stood by [Amasa] and said, He that favours Joab, and he that is for David, let him follow Joab. 12 Now Amasa wallowed in blood in the midst of the highway. And when the man saw that all the people stood still, he removed Amasa out of the highway into the field, and cast a cloth upon him, when he saw that every one that came by stood still. 13 When he was removed out of the highway, all the people went on after Joab, to pursue after Sheba the son of Bichri,
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.