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 20:9-10

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. 20:10 Amasa did not protect himself from the knife in Joab’s other hand, and Joab stabbed him in the abdomen, causing Amasa’s intestines to spill out on the ground. There was no need to stab him again; the first blow was fatal. Then Joab and his brother Abishai pursued Sheba son of Bicri.

Psalms 28:3

28:3 Do not drag me away with evil men,

with those who behave wickedly,

who talk so friendly to their neighbors,

while they plan to harm them!

Psalms 55:20-21

55:20 He attacks his friends;

he breaks his solemn promises to them.

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.