2 Samuel 3:27

3:27 When Abner returned to Hebron, Joab took him aside at the gate as if to speak privately with him. Joab then stabbed him in the abdomen and killed him, avenging the shed blood of his brother Asahel.

2 Samuel 11:13-15

11:13 Then David summoned him. He ate and drank with him, and got him drunk. But in the evening he went out to sleep on his bed with the servants of his lord; he did not go down to his own house.

11:14 In the morning David wrote a letter to Joab and sent it with Uriah. 11:15 In the letter he wrote: “Station Uriah in the thick of the battle and then withdraw from him so he will be cut down and killed.”

2 Samuel 20:9

20:9 Joab said to Amasa, “How are you, my brother?” With his right hand Joab took hold of Amasa’s beard as if to greet him with a kiss.

Psalms 55:21

55:21 His words are as smooth as butter,

but he harbors animosity in his heart.

His words seem softer than oil,

but they are really like sharp swords.