Mencius. Book 4, Part 1, Chapter 20.
Book 4, Le Low. Part 1.
Mencius said, "It is not enough to remonstrate with a soveriegn on account of the mal-employment of ministers, nor to blame errors of government. It is only the great man who can rectify what is wrong in the sovereign's mind. Let the prince be benevolent, and al his acts will be benevolent. Let the prince be righteous, and all his acts will be righteous. Let the prince be correct, and everything will be correct. Once rectify the prince, and the kingdom will be firmly settled."
Text source: The Works of Mencius. Translated by James Legge.