Twenty and five years old was he when he began to reign; and he reigned twenty and nine years in Jerusalem. His mother's name also was Abi, the daughter of Zachariah.
Twenty and five years old As Ahaz was
20 years old when he began to reign, and died when he had reigned
16 years, his whole age only amounted to
36 years; and as Hezekiah was, at least, entering on his
25th year when he began to reign, then Ahaz must have been under
12 years of age when his son was born! This is not at all impossible: and there are well-attested facts of men having children at as early a period, especially in eastern countries.
2 Chronicles 29:1 Hezekiah began to reign when he was five and twenty years old, and he reigned nine and twenty years in Jerusalem...