1 Chronicles 20 · a question people ask
If David stayed at Jerusalem, how did he take the crown?
The chapter says both, and doesn't join them. "But David stayed at Jerusalem. Joab struck Rabbah, and overthrew it" (20:1). Then "David took the crown of their king from off his head" (20:2), and at the end of 20:3, "Then David and all the people returned to Jerusalem" (20:3). 1 Chronicles doesn't tell of David going to Rabbah. 2 Samuel does: Joab sent messengers to David, "gather the rest of the people together, and encamp against the city and take it; lest I take the city, and it be called by my name" (2 Samuel 12:28), and "David gathered all the people together and went to Rabbah, and fought against it and took it" (2 Samuel 12:29). This answer sets the two books side by side and doesn't add to either.
The verses
“Now Joab fought against Rabbah of the children of Ammon, and took the royal city. Joab sent messengers to David, and said, “I have fought against Rabbah. Yes, I have taken the city of waters. Now therefore gather the rest of the people together, and encamp against the city and take it; lest I take the city, and it be called by my name.” David gathered all the people together and went to Rabbah, and fought against it and took it.”