SEV Biblia, Chapter 20:9
Y Joab dijo a Amasa: ¿Tienes paz, hermano mío? Y tomó Joab con la diestra la barba de Amasa, para besarlo.
John Gill's Bible Commentary
Ver. 9. And Joab said to Amasa , etc.] In a friendly manner, with all the air of pleasantry and good humour: [art] thou in health, my brother ? this looked like a friendly salutation to ask of his health, and wish him it, and a loving appellation to call him brother; though they were near of kin, sisters’ children, and so own cousins; thus he addressed him, to cover his design: and Joab took Amasa by the beard with his right hand to kiss him : as was usual for the eastern people to do when they addressed and saluted one another in an affectionate way, and as the Turks and Arabs do to this day, as travellers relate. Barthius has collected passages from the Greek poets, which show it to be a custom, that when a man asked a favour of another, he caught hold of his beard with the right hand, and of his knee with the left; and in such a posture Joab might easily do what follows.
Matthew Henry Commentary
Verses 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 kin 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.
Original Hebrew
ויאמר 559 יואב 3097 לעמשׂא 6021 השׁלום 7965 אתה 859 אחי 251 ותחז 270 יד 3027 ימין 3225 יואב 3097 בזקן 2206 עמשׂא 6021 לנשׁק׃ 5401