2 Samuel 2:20

“Then Abner looked behind him, etc.] Perceiving one at his heels, and making haste up to him. And said, [art] thou Asahel? for it seems he knew him personally, being well acquainted with his family: and he answered, I [am]; so that they were very near to each other, as to discourse together, and be heard and understood by each other.”

“2:20-22 Go fight someone else! . . . Get away from here! Abner’s words reflect respect between peers trained for the same career, as well as a sense of fair play. The youthful Asahel would have been no match for the more experienced Abner. Abner also knew that if he killed Asahel, the conflict with David would escalate and David’s forces would seek revenge (see 3:22-39).”

“Then Abner turned round, asked him whether he was Asahel, and said to him, "Turn to thy right hand or to thy left, and seize one of the young men and take his armour for thyself," i.e., slay one of the common soldiers, and take his accoutrements as booty, if thou art seeking for that kind of fame. But Asahel would not turn back from Abner. Then he repeated his command that he would depart, and added, "Why should I smite thee to the ground, and how could I then lift up my face to Joab thy brother?" from which we may see that Abner did not want to put the young hero to death, out of regard for Joab and their former friendship. 2 Kings (2 Samuel) 2:23”