Matthew Henry, in his commentary, gives us a useful summary of this chapter.
‘Here is a repetition of the story of David’s wars, 1. With the Ammonites, and the taking of Rabbah, 1 Chronicles 20:1-3. 2. With the giants of the Philistines, 1 Chronicles 20:4-8.’
The parallel passages to these verses are found in 2 Samuel 11:1 and 2 Samuel 12:26-30, however, here, the writer doesn’t mention David’s sin with Bathsheba or the killing of her husband Uriah, 2 Samuel 11:4-12:24.
Coffman, in his commentary, says the following.
‘This chapter marks a terrible turning point in David’s life. Not only is there the matter of his torturing the Ammonites, but his adultery with Bathsheba, and his heartless murder of Uriah the Hittite and seventeen of his fellow soldiers in a vain effort to hide his sin, all took place in connection with this siege of Rabbah. The bad days of David’s life began right here.’
Notice that it’s springtime, which means it is time for war, a time when the king should leave his home and lead his men into war. As king, David should have been leading his army in this war against the Ammonites. However, on this occasion, David decides to stay at home in Jerusalem but we’re not told why.
2 Samuel 12:24-31 tells us as Joab was fighting against Rabbah of the Ammonites he sends word back to David about what he’s achieved. He had taken the city’s water supply which meant the city couldn’t function without it.
The city of waters was the name of the fortification built to protect the fountain that still flows in Amman the capital of Jordan. Joab’s loyalty to David is very evident here because he could have easily taken the city himself but he wanted David to get involved so that David could receive the glory for taking the city.
David proceeds to take the crown from the king’s head, the word king used here has a footnote in most Bibles which informs us it was taken from ‘Milcom’s’ head, which was also the name of the national idol of the Ammonites, Amos 1:15 / Zephaniah 1:5.
Because of the precious stones inlaid on it, the crown itself weighed around 125 pounds, which is quite heavy and I don’t believe we are to think that David was going to wear this permanently on his head.
After defeating all the Ammonite towns, David took the spoils of war and then makes them slaves and puts them to work, whilst he and his men return to Jerusalem.
Notice the text says that ‘Elhanan killed Goliath’. For many, this appears to be a contradiction because 1 Samuel 17:50-51 tells us that David killed Goliath.
F Payne, in his commentary, suggests the following.
1. The parallel account in 1 Chronicles 20:5 states that Elhanan killed Lahmi the brother of Goliath.
2. Elhanan and David were names of the same individual, just as Solomon was also named Jedidiah, 2 Samuel 12:24.
3. It is also possible that Goliath was a name worn by more than one Philistine giant, or that it was a Philistine title, or that it described a certain type of Philistine soldier.
These four men mentioned here were descended from the giants in Gath, and they fell by the hand of David and by the hand of his servants. Significantly, David is mentioned here as one who had a hand in killing these giants, which perfectly harmonises with 1 Samuel 17:50-51.
This could possibly be the reason why David took five smooth stones from a river to kill Goliath, not just one, 1 Samuel 17:40, it’s possible that David thought that Goliath’s four brothers might come for him after killing Goliath.
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