Is this one-
Here’s the full quote from which that excellent snippet is extracted:
He has accomplished what he was called to do. He has introduced among us [the knowledge of] languages, and has called us away from the sacrilegious studies. Perhaps he himself will die with Moses in the plains of Moab, for he does not advance to the better studies (those which pertain to piety). I greatly wish he would restrain himself from dealing with Holy Scripture and writing his Paraphrases, for he is not up to this task; he takes the time of [his] readers in vain, and he hinders them in studying Scripture. He has done enough in showing us the evil. He is (in my opinion) unable to show us the good and to lead us into the promised land. But why do I talk so much of Erasmus? Only so that you will not be influenced by his name and authority, but rather be happy when you feel that something displeases him in this matter of Scripture. For he is a man who is unable to have, or does not want to have, a right judgment in these matters, as almost the whole world is beginning to perceive of him.*
*Martin Luther, Luther’s Works, Vol. 49: Letters II (ed. Jaroslav Jan Pelikan, Hilton C. Oswald, and Helmut T. Lehmann; vol. 49; Philadelphia: Fortress Press, 1999), 44. Text in Latin: WA, Br 3, 96–97. Emphasis mine.