1.
“And in the twentieth year of Jeroboam king of Israel reigned Asa over Judah” (1 Kings xv, 9).
As Jeroboam reigned twenty-two years, he reigned two years after Asa became king. From the commencement of Asa’s reign, then, to the death of Ahaziah, the reigns of Israel’s kings were as follows: Jeroboam 2 years, Nadab 2 years, Baasha 24 years, Elah 2 years, Omri 12 years, Ahab 22 years, and Ahaziah 2 years. 2 years + 2 years + 24 years + 2 years + 12 years + 22 years + 2 years = 66 years.
As Asa reigned forty-one years and Jehoshaphat reigned twenty-five years, from the commencement of Asa’s reign to the death of Jehoshaphat was 41 years + 25 years = 66 years.
If from the commencement of Asa’s reign to the death of Ahaziah was sixty-six years, and from the commencement of Asa’s reign to the death of Jehoshaphat was sixty-six years, Jehoshaphat therefore died in the same year that Ahaziah died.
2.
“Now in the eighteenth year of King Jeroboam the son of Nebat reigned Abijam over Judah” (1 Kings xv, 1).
As Jeroboam reigned 22 years, he reigned four years after the beginning of Abijam’s reign. From the beginning of Abijam’s reign, then, to the death of Ahaziah, the reigns of Israel’s kings were: Jeroboam 4 years, Nadab 2 years, Baasha 24 years, Elah 2 years, Omri 12 years Ahab 22 years, and Ahaziah 2 years. 4 years + 2 years + 24 years + 2 years + 12 years + 22 years + 2 years = 68 years.