Contradiction with 1 Chronicles 21:18
This verse also describes the command from the angel of the Lord to David to build an altar, but the context and events leading to this moment differ in the accounts between 2 Samuel and 1 Chronicles.
1 Chronicles 21:18: Then the angel of the LORD commanded Gad to say to David, that David should go up, and set up an altar unto the LORD in the threshingfloor of Ornan the Jebusite.
Paradox #1
The contradiction or inconsistency related to 2 Samuel 24:18 is that there is a parallel account in 1 Chronicles 21:18, where certain details differ between the two stories. Specifically, there are differences in who incites David to take a census, differences in the numbers reported, and variations in the narrative details surrounding the event. These discrepancies can lead to confusion about the historical accuracy and consistency between the two accounts.