2 Samuel 24:8-10

8In that way, they travelled through the whole country. After nine months and 20 days they returned to Jerusalem.

9Joab reported to the king about the number of soldiers who could fight. There were 800,000 men in Israel who could use a sword to fight. There were also 500,000 soldiers in Judah.

10David had counted the men who were able to fight in his army. But now he was sorry that he had done it. He said to the Lord, ‘What I have done was a bad sin. Please forgive me, Lord. I have done a foolish thing.’