The length of David's reign over Israel was forty years--seven years in Hebron and thirty-three years in Jerusalem.

2 Samuel 5:4
David was thirty years old when he became king, and he reigned forty years.

2 Samuel 5:5
In Hebron he reigned over Judah seven years and six months, and in Jerusalem he reigned thirty-three years over all Israel and Judah.

1 Kings 2:11
The length of David's reign over Israel was forty years--seven years in Hebron and thirty-three years in Jerusalem.

1 Chronicles 3:4
These six sons were born to David in Hebron, where he reigned seven years and six months. And David reigned in Jerusalem thirty-three years,

And the time that he reigned over Israel was forty years; seven years reigned he in Hebron, and thirty and three years reigned he in Jerusalem.