C. F. Keil and Franz Delitzsch on 2 Samuel 20:9-10

2Sa 20:9-10

Joab asked Amasa how he was, and laid hold of his bear with his right hand to kiss him. And as Amasa took no heed of the sword in Joab’s hand, he smote him with it in the paunch (abdomen), and shed out his bowels upon the ground, “and repeated not (the stroke) to him” (cf. 1Sa 26:8). Laying hold of the beard to kiss is still customary among Arabs and Turks as a sign of friendly welcome (vid., Arvieux, Merkwürdige Nachrichten, iv. p. 182, and Harmar, Beobachtungen, ii. p. 61). The reason for this assassination was Joab’s jealousy of Amasa. Joab and Abishai then followed Sheba.