[Essay] Karl Barth, “Rousseau”, Chapter II of Karl Barth, Protestant Thought: from Rousseau to Ritschl (Translated by Brian Cozens from eleven chapters of Die Protestantische Theologie im 19. Jahrhundert) Harper & Brothers: New York, 1959, p 58-117

Excerpt:

With Jean-Jacques Rousseau, in the middle of the eighteenth century,  the new age begins which we call the age of Goethe, the age which  presented Protestant theology after Schleiermacher with the problem  with which it chose to concern itself, and which also largely supplied  the answer it thought fit to give. The new age in the middle of the eighteenth century! There are two things implied here from which follow  significant principles which must be borne in mind in interpreting  Rousseau. Not to understand him as a child of his century, who for all  his individuality could not help but participate very energetically  after his own fashion in its general and characteristic trends, would be  to understand him falsely. But we would be understanding him even  less if we failed to realize that it was precisely as a child of his century  that he fought, passionately and radically, against its most typical  tendencies, and consummated a completely different new movement  in opposition to them. We must be so careful in assessing him because  as an event he contains a paradox. He was not merely incidentally a  man of the eighteenth century. He was one very definitely, in a way  which made him both bolder and more consistent than almost all those  about him, and it was precisely in this way that he contradicted and  rose above eighteenth-century man and, on the other hand, he contradicted and rose above eighteenth-century man in no other way than  this that it was in Rousseau himself that eighteenth-century man  achieved fulfillment. There are similar things which we shall have to  say later of Lessing and Kant. They must be stated with particular  emphasis in the case of Rousseau because as a historical figure he is  attacked much more from both sides; and indeed he is much more open  to attack.

Online:
Protestant Thought: From Rousseau to Richtl [pdf]