2 Samuel 8:4
NKJV: David took from him one thousand chariots, seven hundred horsemen, and twenty thousand foot soldiers. Also David hamstrung all the chariot horses, except that he spared enough of them for one hundred chariots.
NASB: David captured from him 1,700 horsemen and 20,000 foot soldiers; and David hamstrung the chariot horses, but reserved enough of them for 100 chariots.
1 Chronicles 18:4
David captured a thousand of his chariots, seven thousand charioteers and twenty thousand foot soldiers. He hamstrung all but a hundred of the chariot horses.
This is a copyist error (see the translation footnotes). The general consensus is that 7000 is the correct number (which makes sense, since the 2 Samuel number has varied and the 1 Chronicles number has not).
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