Bossuet: "Two ways of aspiring to the reformation of the Church"

There were thus [prior to the 16th century] two different sorts of persons who called for reformation: one, the truly peaceful and true children of the Church, without bitterness supporting her grievances, and who, with respect, proposed a reformation of them, and in humility bore them despite its delay.

Far from desiring to effect this object by schism, they, on the contrary, looked on schism as the greatest of all evils. In the midst of these abuses, they admired the Providence of God, who, according to his promises, knew how to preserve the faith of the Church.

And, though they could not accomplish a reformation of attitudes, free from all bitterness, and free from all passion, they deemed themselves glad that nothing prevented them from accomplishing it within themselves. These were the strong ones of the Church, whose faith no temptation could shake, nor induce to deviate from unity.

Besides these, there were proud spirits, who, shocked by the disorders they saw prevailing in the Church, particularly in her ministers, did not understand how the promises of her eternal duration could subsist in the midst of such abuses; whereas the Son of God had taught to respect for  the chair of Moses, notwitstanding the evil works of the Scribes and Pharisees who sat upon it; these became proud, and thereby weak, yielding to the temptation which inclines to hate the Chair itself, due to the hatred towards those who preside upon it; and, as if the wickedness of man could make void the work of God, the aversion they had conceived against the Doctors made them hate both the doctrines they taught and the authority they had received from God to teach.

Such were the Waldensians and Albigensians; such were John Wycliffe and Jan Hus. The ordinary bait by which they induced weak souls into their webs was the hatred with which they inspired them against the Pastors of the Church; influenced by this spirit of bitterness, they desired nothing but rupture.

Jacques-Bénigne Bossuet
Histoire des variations des églises protestantes