He in the first year of his reign, in the first month, opened the doors of the house of the LORD, and repaired them.
In the first year of his reign, in the first month - not the first month after his accession to the throne, but in Nisan, the first month of the sacred year, the season appointed for the celebration of the Passover.
Opened the doors of the house of the Lord - which had been closed up by his father (2 Chronicles 28:24).
And repaired them - or embellished them (cf. 2 Kings 18:16).