John Gills Exposition of the Bible Commentary - 2 Chronicles 11:17
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... read more
Matthew Henry's Complete Commentary - 2 Chronicles 11:13-23
See here, I. How Rehoboam was strengthened by the accession of the priests and Levites, and all the devout and pious Israelites, to him, even all that were true to their God and their religion. 1. Jeroboam cast them off, that is, he set up such a way of worship as he knew they could not in conscience comply with, which obliged them to withdraw from his altar, and at the same time he would not allow them to go up to Jerusalem to worship at the altar there; so that he totally cast them off from... read more