13.
“In the fiftieth year of Azariah king of Judah, Pekahiah the son of Menahem began to reign over Israel” (2 Kings xv, 23).
From the death of Ahaziah to the accession of Pekahiah, Israel’s kings reigned as follows: Jehoram 12 years, Jehu 28 years, Jehoahaz 17 years, Joash 16 years, Jeroboam 41 years, Zachariah and Shallum 1 year, Menahem 10 years. 12 years + 28 years + 17 years + 16 years + 41 years + 1 year + 10 years = 125 years.
From the death of Jehoshaphat to the accession of Pekahiah, Judah’s kings reigned as follows: Joram 8 years, Ahaziah 1 year, Athaliah 6 years, Joash 40 years, Amaziah 29 years, Azariah 50 years. 8 years + 1 year + 6 years + 40 years + 29 years + 50 years = 134 years.
If from the death of Ahaziah to the accession of Pekahiah was one hundred and twenty-five years, and from the death of Jehoshaphat to the accession of Pekahiah was one hundred and thirty-four years, Jehoshaphat therefore died nine years before Ahaziah died.