2 Chronicles 11:17 - Wesley's Explanatory Notes

So they strengthened the kingdom of Judah — Not only by the addition of so many persons to it: but by their piety and prayers they procured a blessing upon the kingdom which was a sanctuary to them. They made him strong three years; for so long he served God; but when he forsook God, none could strengthen him. We retain our strength as long as we cleave to God and our duty, and no longer. And Solomon — This honourable mention of Solomon, as a pattern of piety, is a considerable evidence of his true repentance before his death.