20:1 In the spring, at the time when kings normally conduct wars, Joab led the army into battle and devastated the land of the Ammonites. He went and besieged Rabbah, while David stayed in Jerusalem. Joab defeated Rabbah and tore it down. 

David sent sympathy ambassadors to Ammon in order to recognize the death of their king. Ammon responded by insulting the Israeli ambassadors by cutting off their beards and exposing them to public nudity from the waist down. Joab defeated the Ammonites for this insult, but the war continued into the spring. 

David remained in Jerusalem. During this time, David murdered Uriah and committed adultery with Bathsheba. The Holy Spirit did not record this specific event in Chronicles, because the sin has been confessed by David and forgotten by God.

There is an idea in the modern satanic culture that right and wrong can walk together. God disagrees. “Can two walk together, except they be agreed?” (Amos 3:3). If a believer is walking with evil, it is because he has compromised with it. When one walks with evil, then he is agreeing with evil. Many people will protest war, but they will not protest lawlessness in their own streets. Evil must be exposed and opposed. Heresy is the worst kind of evil, because it is an attack on the Word of God. Heresy must be exposed and opposed, especially if it is alive and taught inside of local churches. Right and wrong are in opposition. There cannot be an agreement between the two.

20:2 David took the crown from the head of their king and wore it (its weight was a talent of gold and it was set with precious stones). He took a large amount of plunder from the city. 

It was the king’s responsibility to lead his armies in battle. While David was murdering his soldiers in Jerusalem and committing adultery, Joab was about to take this Ammonite city and receive credit for the victory. General Joab reminded his king that he needed to leave Jerusalem and come claim the military victory in Ammon.

20:3 He removed the city’s residents and made them do hard labor with saws, iron picks, and axes. This was his policy with all the Ammonite cities. Then David and all the army returned to Jerusalem. 

The Ammonites wanted to defeat Israel and make them slaves. This was a violation of the Abrahamic Covenant. Instead, it was the Ammonites who who were defeated and enslaved.

20:4 Later there was a battle with the Philistines in Gezer. At that time Sibbekai the Hushathite killed Sippai, one of the descendants of the Rephaim, and the Philistines were subdued. 

Before David, Israel never could defeat the Philistines. Samson was a judge who was given divine supernatural power to defeat the Philistines, but his sin caused him to be blinded and enslaved by them. King Saul could never defeat them. David defeated them every time he fought them, because he always sought the Lord’s will before the battle.

20:5 There was another battle with the Philistines in which Elhanan son of Jair the Bethlehemite killed the brother of Goliath the Gittite, whose spear had a shaft as big as the crossbeam of a weaver’s loom. 

Goliath was a giant who had five brothers. Elhanan the Bethlehemite killed one of his brothers in battle. This may have been another one-on-one-winner-take-all confrontation, similar to that of David and Goliath.

20:6 In a battle in Gath there was a large man who had six fingers on each hand and six toes on each foot—twenty-four in all! He too was a descendant of Rapha. 

The Rapha were a race of giants who may have intermarried with the Philistines.

20:7 When he taunted Israel, Jonathan son of Shimea, David’s brother, killed him. 

This death may have been the result of another one-on-one-winner-take-all battle between Israel and the Philistines. Satan raised up his giants to mock God, but God answered with men who feared God rather than the enemy.

20:8 These were the descendants of Rapha who lived in Gath; they were killed by the hand of David and his soldiers.

This giant race was killed by David and his soldiers. They no longer exist today. These giants were a threat to the human race, because Satan would train them for battle so that they could threaten the existence of Israel. It was predicted in Genesis 3:15 that a Messiah would be born of a virgin and He would crush the head of Satan. Therefore, Satan has always attempted to exterminate Israel with giants, armies, and seductive pagan religions. He has tried many methods unsuccessfully in order to keep the Messiah from being born.