Does David trust Abner or is David just being diplomatic? We do not know for sure, but it is possible that David could have known Abner quite well. They could have previously fought together in Saul’s army.
Joab murders Abner
Joab acts out of revenge for the death of his brother Asahel. But David wants to make clear that he has played no part in this murder. This may be a political gesture. However, David might well be speaking honestly when he describes Abner as a ‘commander and a great man’ (3:38).
Why does David execute two men who were only trying to fulfil God’s promise?
A modern reader might accuse David of being barbaric in the way he treated Rekab and Baanah. They might have thought they were doing God’s will by killing David’s enemy. Or they might have had the motive of trying to get a position of influence in return for supporting David. But David considers them as criminals and he wants others to be afraid to copy their actions. Ish-Bosheth is not fighting or organising wars. He is a puppet-king lying in his bed. God has not told anyone to kill Ish-Bosheth; Rekab and Baanah have entered his house uninvited and murdered him in cold blood. According to the Law of Moses, the penalty for murder is death (Exodus 21:12 and Leviticus 24:17).
What can we learn from David’s actions?
In addition to waiting fifteen years from Samuel’s anointing until his anointing as king over Judah, David had to wait seven and a half more years before becoming king over all Israel. This is an example to us of patience. We don’t need to grab what God has promised us. Joab, Rekab and Baanah are an example of how not to behave. We don’t need to manipulate, scheme or force situations to get what we want. We must have respect for human life. We should also have respect for people in authority, even if they are making our life difficult.
The life of David foreshadows the life of Jesus. David endured rejection and suffering before establishing his kingdom. Similarly, Jesus endured rejection and suffering before establishing his kingdom. God is calling us to have the same mindset as Jesus (Philippians 2:1-11).