In the eighth year of his reign, while he was still young, he began to seek the God of his ancestor David. In the twelfth year of his reign, he began to remove the high places, Asherim, carved images, and cast images from Judah and Jerusalem.

Ahaziah was 22 years old when he became king, and he reigned for one year in Jerusalem. His mother was Athaliah, Omri's granddaughter.

He launched a military excursion against the king of the Ammonites and defeated him. As a result, that year the Ammonites paid 100 talents of silver in tribute, as well as 10,000 kors of wheat and 10,000 kors of barley. The Ammonites continued to pay this same amount in tribute over the following two years.