Though the NIV gives concrete figures, the Hebrew text itself is unclear. Indeed, the numbers which specify how old Saul was when he began to reign, as well as the time which he reigned are lacking in the Masoretic Text and the Septuagint (LXX).1 The idea that Saul was thirty years old stems from the fact that he was a young man when Samuel anointed him as king (see 1 Samuel 9:2; 1 Samuel 10:1). The idea that Saul reigned forty-two years is based on the date mentioned by the apostle Paul in Acts 13:21.2
1 Saul lived for one year and then became king, and when he had reigned for two years over Israel,