So they strengthened the kingdom of Judah,.... Made it more numerous, and in a better condition to defend itself: and made Rehoboam son of Solomon strong three years; established him on the throne, strengthened the government in his hands, and were the means of preserving him in the pure worship of God for the space of time mentioned, the reason of which follows: for three years they walked in the way of David and Solomon; in their good ways, which were according to the rule of the divine word; and which, as they refer to the whole of David's life and reign, some particular actions excepted, so to the former part of Solomon's reign, before he fell into idolatry, and to the latter part of it after his repentance; for that he did repent is by some concluded from hence, and may be more strongly from the book of Ecclesiastes, written by him in his old age. This is to be understood both of Rehoboam and his people, who after three years forsook the law of the Lord, Ch2 12:1.